Pesticide residues can be found in the foods we consume in food, fruit, and vegetables, in water and air, and as a result, negative consequences for human health can occur. It is important for food that reaches the market to be safe, and any pesticide residues that may be present must be within the maximum permitted concentrations, which is regulated in the Republic of Croatia by Regulation no. 396/2005 of the European Parliament and the Council of February 23, 2005, on maximum levels of pesticide residues in food and animal feed of plant and animal origin. The aim of this thesis was to determine the presence of pesticides in fruit and vegetable samples found on the market of the Republic of Croatia. The concentration of pesticides in fruits and vegetables was determined by the instrumental techniques of gas chromatography with a mass spectrometer, gas chromatography with an electron capture detector, and liquid chromatography with a mass spectrometer. Out of a total of 142 analysed fruit and vegetable samples, pesticide residues above the maximum allowed concentrations were detected in 8 samples. Such samples did not pose a risk to human health. Given that fruits and vegetables are used daily in the diet, the safety of these products is of public health importance. It is necessary to carry out regular controls over pesticides in fruits and vegetables.