Different pesticide residues (carbofuran, carbosulfan, methomyl, malation, silycron and cypermethrin) were extracted from treated samples of tomatoes fruits and potatoes tubers before and after food processing. GLC, spectrophotometric and enzymatic methods were used to determine pesticide residues in different samples.    Pesticide residues for all pesticides were detected with the previous methods with some variation in results depending on the methods sensitivity. The pesticide residues concentration in potatoes tubers were ranged between 8.74 and 7.24 ppm for cypermethrin and malathion with using spectrophotometric methods, while these residues concentrations were ranged between 8.407 and 7.79 ppm for carbofuran and malathion by using enzymatic methods. Silycron residues was 8.3 ppm with using GLC.  Also the same parameters was used with tomatoes fruits. The detected concentrations for malathion was ranged between 8.22 and 0.534 ppm with used spectrophotometric methods before and after food processing. The detected pesticide residues of methomyl and malathion were used  to determine their effects on some enzymes activities (in vivo).Results showed that all concentrations were affected gradually on  the alanine amino transaminase (ALT), aspartate amino transaminase (AST), acid phosphatase, alkaline phosphatase and acetyle cholinestrase (AchE) activities.