A total of 105 samples consisting of 10 raw sesame seed samples were collected from different places of Egyptian Govemorates (Cairo. Giza. Qalubia Gharbia. Portsald. Ismailia. and Dakahlia). Additional. 35 randomly Halaw Tehinia (HT.) and Tehina (T.) samples processed by some authorized registered(R) and non authorized unregisteredwR) Egyptian producing factodes=were purchased from Cairo retail markets. The samples were collected during autumn and winter seasons of 200412005. All samples were examined for the contamination of aflatoxins. The chemical composition. fatty acids pattern of the oils extracted from raw sesame seed. HT. and T. were studied. Also amino acids concentrations in the main products were determined. Results showed that raw sesame seeds. R.HT., and RT. samples were almost free from aflatoxlns in most samples. On the other hand. most of H.T. samples produced from illegal factories (UR.HT.) were contaminated with aflatoxin. The reason of such contamination were studied. The discussion is presented showing that. it is highly probably that peanut and palm oil were used in the manufacturing of U'R.HT. to replace part of sesame seed.