Field evaluation for the efficacy of indoxacarb, spinetoram and methoxyfenozide against larval instars of S. littoralis, infested clover plants Trifoliuma lexandrium was studied at two different Governorates (Al- Qalyubia and El- Fayoum) during cultivation season 2012 - 2013.All three insecticides, of indoxacarb, spinetoram and methoxyfenozide had no great difference among themselves in reducing the larval population of S. littoralis with difference in the time needed to induce this reduction according to the mode of action of these insecticides.The initial reductionwas recorded after 1 day from spraying for indoxacarb and spinetoram while after 3 days from spraying for methoxyfenozide. Indoxacarb was the most effective insecticide followed by methoxyfenozide and spinetoram.Under semi-field conditions, results showed that, at Al- Qalyubia Governorate, persistence of indoxacarb is higher than other tested insecticides while, the half life of all tested compounds is short at El-Fayoum Governorate.Tolerance to the toxicity of the three tested insecticides increased as the larvae grew older from 2^nd to 4^thinstar.Biochemical clarification was carried out in an attempt to disclose the effect of sub-lethal concentration (LC₅₀) of the three tested insecticides; on haemolymph contents of 6^th instar larvae of S. littoralis which was treated as 4^thlarval instar with LC₅₀ of the tested insecticides and their effects on main components of insect metabolites and changes in protein patterns.