The biochemical studies were carried out on  larvae, pupae and adult stages of four Med-fly  genotypes, i.e.  two laboratory strains (dark and yellow pupae), genetic sexing line (G.S.) and wild strain. Isoelectrophoresis of Alkaline phosphatase (AP), Esterase and Polyphenol oxidase enzymes were determined with further genetic variations, for their controlling of physiological reaction. Results of electrophoresis indicated that four zones of isozyming bands in Alkaline phosphatase are designated according to the migration from the origin line. The functional genes of Alkaline phosphatase isoenzymes of larvae were higher in band numbers and activities than in pupae and adult extractions in all materials. The highest activity  units of bands were found  in extraction of the adult male samples of  (G.S.) line. No great variations were found between males and females in wild genotype and the two lab. strains.  The esterase isozymes showed three banding zones designated corresponding to the migration from the origin line in all extracted materials. The  genes controlling the activity of isoesterases varied from banding  zone to another according to the stage of development. The first zone of larval stage, and the second zone of pupal stage were more active than the other zones, while, all the three zones were more active in adult stage. For polyphenol oxidase isozymes the two methods used of enzymatic analysis indicated that larval stage was  more active than in  other stages, The yellow pupae strain and (G.S.) line showed activity in  polyphenol oxidase enzyme than the other genotypes.