Natural abundance and biocontrol efficiency of the endoparasitoids O. pallipes and C.parksi was studied in four tomato greenhouses in Alzawia region. O. pallipes recorded two peaks of abundance in all greenhouses, the highest peak recorded ( 7, 5, 7 and 7 individuals/ 50infested leaflets) in greenhouses 1,2,3 and 4 respectively , while the highest average numbers occurred in April in all greenhouses recording (4.5± 2.1 , 3.1± 1.6 , 4.5± 2.2 and 4.5±2.1 individuals/ 50infested leaflets) in greenhouses 1,2,3 and 4 respectively, while percentages of parasitism reached (30.4%, 38.5% , 31.6% and 30.4%) in greenhouses 1,2,3 and 4 respectively. C.parksi recorded two peaks of abundance in all greenhouses, the highest peak recorded ( 8, 7, 7 and 6 individuals/ 50infested leaflets) in greenhouses 1,2,3 and 4 respectively , while the highest average numbers occurred in April in greenhouses 1and 4 recording ( 5.3± 2.1 and 5.2±2.2 individuals/ 50infested leaflets) respectively and in march in greenhouses 2and 3 recording ( 4.1± 1.4 and 4.0±1.4 individuals/ 50infested leaflets) respectively, while percentages of parasitism reached (38.1%, 36.8%, 27.7% and 38.1%) in greenhouses 1,2,3 and 4 respectively.The parasitoids showed high populations in April and May the study that kept the populations of the serpentine leaf miner L.trifolii at low densities till the end of the season in all studied greenhouses