Today, contamination of agricultural products with fungal toxins, especially aflatoxins, is considered one of the most important health problems and a global concern in food safety. Contamination of pistachios with species of fungi of the Flaviaceae family and aflatoxins has led to restrictions on their export to European Union countries. One of the main management strategies to combat the formation of aflatoxins in agricultural products in the pre-harvest stage is the evaluation of the resistance of pistachio varieties to the fungus Aspergillus flavus and its relationship with the amount of chemical compounds of pistachio varieties. For this purpose, in this study, by measuring the amount of fat and fatty acids in the kernels of pistachio varieties, the possible relationship between the amount of these compounds and the resistance of the kernels of pistachio varieties to the growth of aflatoxin-producing fungi was investigated. Pistachio kernel fat was measured by the Soxhlet method and the type and amount of fatty acids were measured by gas chromatography (GC). In order to investigate the relationship between fat and fatty acids in pistachio kernels of various cultivars and the growth rate of A. flavus and aflatoxin production, the correlation coefficient (r) was calculated. The results of statistical studies showed that there was no statistically significant relationship between the growth rate of A. flavus and aflatoxin production and the amount of fat and types of fatty acids in pistachio kernels of various cultivars. Many other chemical and physical factors may be involved in this.