The introductory part hereof describes the pressure exerted to agriculture and the processing industry in order to provide for the enough food for the ever growing mankind. Although the food production is considered as the basic incentive in the global environmental changes, every year one third of the global food supply still either goes to waste. The Europe Union only looses 90 million tons of food annually where even 53% of this quantity is produced by the households. Accordingly it is rather necessary to direct the strongest attention to the behavior of the consumers. At the end of the introductory part the goals and purposes are defined. The purpose of this paper is to establish the quantity of food waste in the Croatian households. Further, it is considered necessary to test the extended Theory of Planned Behaviour model (hereinafter TPB) within the household food waste behaviour context and to establish, as well, the influence exerted by knowledge, the habits and the socio-demographic characteristics of the household members when speaking of the quantity and the type of the household waste. In the chapter Overview of the previous Research the course of the food waste research development is presented stressing the findings on the main indicators of the household food waste connected to the consumer behaviour. The emergence of the waste through the contribution of various supply chain phases in the actual total food waste quantity is explained and the food waste management system is presented with the main process types. The definitions of the food waste are offered as well as the quantification and qualification of food waste originating from the households. The reasons for the food waste occurrence on the consumers’ levels are given, following from the standpoints, attitudes, habits knowledge and skills, the socio-demographic facts, the legislature, situation management, consumer and consumption trends and the marketing and selling strategies. The notion of the attitude and its role within the TPB is explained in more detail, it being one of the most frequently used theory for forecasting the consumer behavior. According to the TPB the behaviour is determined by three elements: attitudes towards specific behaviour, subjective norm and perceived behavioral control (PBC). Attitude towards specific behaviour refers to the degree indicating a favourable or unfavourable evaluation of the behaviour inI question. Subjective norm refers to the perceived social pressure to perform or to not perform the behaviour, while the perceived behavioral control, refers to the perceived ease or difficulty when performing the behaviour (Ajzen, 1991). The more positive attitudes, the higher subjective norm and higher the level or perceived behavioural control. This also means a higher intention of a certain behavior, while, at the same time, the higher intention and the higher perceived behaviour control mean the actual behavior presentation. At the end of the chapter the research where the TPB was used is given and explained when speaking of the consumer behavior in the area concerned with the food waste. The chapter Material and Methods refers to the course of the research and the processed data are presented as well. In order to gain a more complex insight with the research problem the qualitative and the quantitative methods were combined. In the first step an in-depth interview has been implemented with a sample of 20 examinees. The findings were used for creating a questionnaire for the main poll while the research on the quantities of discarded food was implemented during the second and the thirds step. The poll was pre-tested with a sample numbering 49 examinees. When choosing the research method concerning the discarded quantities a sample of five households was used and three methods available in the literature were predestined – the weighing method, the method of conclusion concerning the waste quantities and the quantity self-evaluation method. The self-evaluation method, regarded as the most successful one, was chosen at the end as the research method concerning the discarded food waste where a number of 118 households followed and reported on the quantities of food waste created as unavoidable and avoidable waste during seven days. After the filled in table has been delivered the representative of the household collecting the data filled in in the questionnaire on the knowledge and the habits when speaking of food treatment and food waste. The results were analyzed by the manifold regression method. The main poll was implemented during the third step. The questionnaire which relies on the TBP concerning the forecast of the behaviour avoiding the discarding of food was distributed through Internet and thus it was filled in by a number if 841 examinees. The results of the survey were analyzed by the statistical SPSS programme. Univariant data analysis (frequency and data distribution) and regression analysis were also implemented. Before the data analysis the scale measurement reliability was tested using Cronbach alpha coefficient while the Structural Equation Modelling (SEM) was used to test the models. The statistical programme Onyx was used to fit the Structural Equation Model. The Chapter Results and Discussion lists the main results as obtained by the quantitative and the qualitative survey. The data concerning the reported food waste quantity on the household level were extrapolated into annual values in order to obtain the annual average Croatian household waste quantity per capita amounting to 75 kg. Almost one half thereof is represented by fruits and vegetables (23% each) then follow inedible parts like egg-shells, tea-leaves and coffee sediments presented as “other” (with 12%), potato, bread and buns (with 9% each), meat (7%) while in the least amount shared pasta with rice and milk and dairy products, represented with 4% each, then fish and readymade dishes (3% singly), cakes and cookies as well as processed fruit and vegetables (2% each). The habits were found to have a certain influence while the knowledge was found to have no influence at all when considering the behaviour concerning food and the type and quantity of food waste. The age of the examinees influences positively the avoidance of waste while the income and number of children under 18 has a negative influence. The results of the poll research pointed to the fact that within the TBP model frame an equally strong influence is exerted by the attitude when speaking of intention, by the subjective norm, the observed health risk and the subjective knowledge on food preservation. Some weaker influence is shown by financial worries connected to discarding food and the habit of planning connected to food while an even less positive influence on behaviour has been observed when speaking on intention has been observed with the TBP. It is expected, taking the TBP model into consideration, that the strongest positive influence on the behaviour will be expressed by intention, a considerably weaker influence is exerted by the good housekeeper role while and even less positive influence has been observed with the perceived behavioral control. The Theory of Planned Behaviour model extended by the financial worry concerning the discarding of food, the observed health risks, the role of a good housekeeper, planning habits and subjective knowledge concerning the use of food explain the 70% of the intent and 96% of the behavior. The results obtained by the SEM method application proved the fact that the attitude, the subjective norm and the PBC influence the intention not to discard food. It was also established that the consumers with a highly expressed intention to avoid discarding food reported less discarded food per household while the intention was found to be the strongest prediction of behaviour in the explanatory extended TPB model. The same finding was confirmed by the research on the discarded quantities where the intention was, according to PBC and the purchase planning and food preparing habit in the households was the strongest behaviour forecasting predictor. In the discussion section, besides comparing the results with those of the previous studies, the business implications were given as well. The research resulted in several important discoveries on the facts concerning consumers behavior connected to the avoidance of food waste discarding to be applied in the practice. The Theory of Planned Behaviour was applied when forecasting the avoidance of food discarding and was for the first time extended with eight additional constructs. This was the first research where the behaviour of the consumers concerning the avoiding of food discarding was studied by using the daily journal method resulting with obtaining the actual quantities and types of the discarded food on the household level. The results of the research are important for the legislature as they offer the information on the role of some single facts important for avoiding the discarding of food on the consumers level but they also indicate the reaching of resolutions which, in the opinion of the consumers, make such behaviour impossible. On the basis of the research results it is possible to forecast the reason why the consumers are ready to avoid the discarding of food and to create according policies motivating such behaviour or leading to the decrease of the discarded food quantities in the households. Although the attitudes concerning the avoidance of discarding food are considered as positive it will be necessary to inform the consumers on the importance of such behavior not only from the saving of the environment point of view but from the economy, ethical responsibility and the social viability point of view as well. It will also be necessary to organize and implement the measures motivating such behavior in the households through a longer period of time. In the discussion section some limitations of research were given. The key limitation of this type of measurement is the measure of behavior where the respondents are expressing their behaviour (self-reported measure). It is considered as probable that the willingness to participate in such research will be found in the areas with better ecology awareness a fact which may have resulted with significantly less self-reported quantities of food waste in the sample households than in the actual situations. Further, the Croatian territory has not been evenly represented a fact which may influence the accuracy of the results taken the uneven development of the Croatian regions into consideration. One should also consider the dominance of the female populations of younger age with high professional qualification and with high or moderate income. Research was implemented during the summer time period and thus one cannot disregard the influence of the seasonal examinees’ alimental habits. The TBP also takes the behavior of single individuals into consideration and thus its constructs were evaluated on the individual level while during the research the behavior was analyzed on the household level. However, as the examinee confirmed the fact that he/she is actually responsible for the purchase of food and food preparing in the household, it is presumed that, accordingly, he/she is also the party responsible for the food proceeding. The research poll sample does not reflect the general population as the examinees were educated parties with higher income. On the other hand the coded statements did not prove to be a best solution for the extended TBP construct model measurement. The measurement instruments volume as well as the number of the constructs and the total number of the questions may have brought to a fatigue among the examinees influencing thus the misinterpretation of the results. The Conclusion gives the main results emerging from the research as a whole. Thus it was concluded that the food waste quantity occurring in the Croatian households is lower than the EU average. The research showed the applicability of the extended Theory of Planned Behaviour when predicting the food waste avoidance.