This study was conducted to evaluate four insecticides; namely methoxyfenozide & chlorfluazuron (as insect growth regulators) and deltamethrin & beta-cyfluthrin (as pyrethroids) against the 2nd and 4th larval instars of Spodoptera littoralis after treatment cauliflower fields in Beheira and Fayoum Governorates under semi-field condition and corrected percentage larval mortality were recorded at intervals. The results in the governorates of Beheira and Fayoum are similar, where in Fayoum Governorate, the mortality percentage of insect growth regulators (methoxyfenozide & chlorfluazuron) declined compared to pyrethroid compounds (deltamethrin & beta-cyfluthrin) post treatment against 2nd & 4th instars, where the mortality percentage were 96 & 92% for deltamethrin and 94 & 91% for beta-cyfluthrin against second & fourth instar larvae, respectively at first day of post treatments (initial kill), and the mortality percentage (initial kill) reached to 69.5 & 67% post treatment with methoxyfenozide and 70.5 & 68% post treatment with chlorfluazuron for second & fourth instar larvae, respectively. In case of residual effect, the mortality percentages for 2nd & 4th instar larvae recorded 65.5 & 65%, 64.5 & 61.5%, 87.5 & 85% and 85.5 & 84% post treatment with deltamethrin, beta-cyfluthrin, methoxyfenozide and chlorfluazuron, respectively. Biochemical studies, indicated that the four tested insecticides caused significant increasing in chitinase activity and the most effective compound was noticed by chlorfluazuron and methoxyfenozide. all tested insecticides caused highly significant reduction at range -34.36 and -52.68% compared to untreated in total proteins. On the other hand, all insecticides achieved high acetylcholinesterase activity compared with untreated and the highest significant increase of acetylcholinesterase activity obtained of deltamethrin followed by beta-cyfluthrin. In case of carbohydrate digestive enzymes (invertase, trehalase and amylase), the amylase enzyme achieved no significantly differences between all treatments and untreated, while the activity of trehalase enzyme was significant decreased as affected by all treatments compare to untreated, Likewise invertase enzyme, it was remarkable decreases in the activity of enzyme for treated with deltamethrin, beta-cyfluthrin and methoxyfenozide, but risen in case of chlorfluazuron.