Due to the climate change caused temperature differences and extremes, combined with various crises in the food industry, the safety of the food we consume is extremely important. In order to achive this we need knowthe concentration of each contaminant that may occur in food and cause adverse effects on humans and animals. Mycotoxins are secondary metabolites of fungi, with low moleular weight, harmful for animal and human health at low concentrations (>mg kg-1 body weight). They have wide spectrum of toxicity: they are neurotoxinc, teratogens, mutagens and immunotoxic. Their presence in food is inevitable and they are most commonly found in cereals. Methods used for analysis must be specific and selective and enable a quick and easy analysis of the contaminants. Therefore, LC-MS/MS method for mycotoxins analysis are increasingly used because they have proved to be comprehensive and sensitive. Before any method can be used, it needs to be validated. Validation determines if the method is fit for it’s purpose and that the mesured result has acceptable uncertainty. The basic validation parametars are accuracy, precision, selectivity, sensitivity, repeatability and stability. It is also adviceble to participate in interlaboratory comparison and to examine the influence of the matrix effect on mycotoxin analysis in order to ensure quality of results.