Benzoic acid is extensively used in the preservation of food products for maintaining quality and extending shelf life by inhibiting mould and bacteria growth. Some previous studies have demonstrated that consumption of excessive amounts of benzoic acid could be a health hazard. The aim of this study was to detect the presence of benzoic acid and its salts in some commercial children food like potatochips that labeled "Free of Preservatives" . Twenty seven samples of potatochips purchased from three different local products were analyzed for the presence of benzoic acid. The results revealed the presence of benzoic acid in nine samples and its concentration was between 100.34-188.65mg/kg. We have concluded also that TLC is a very convenient method for the detection of benzoic acid in food products .