Determination of the effects of different preys on the reproductive biology of Anthocoris nemoralis (F.) (Heteroptera: Anthocoridae) In order to make more effective of mass rearing of Anthocoris nemoralis (F.) (Heteroptera: Anthocoridae), rearing on Ephestia kuehniella Zell. (Lepidoptera: Pyralidae) under laboratory conditions, was aimed in this study. For this reason, the short term effects of different preys on preoviposition period and fecundity of A. nemoralis were investigated. E. kuehniella eggs were supplied for the prey of rearing of A. nemoralis. Tetranychus urticae Koch. (Acarina: Tetranychidae) and Cacopsylla pyri (L.) (Homoptera: Psyllidae)were supplied on third days of adult ages for 24 hours as prey to shorten the preoviposition period and to determine the fecundity. The study was carried out at 25±1°C, 60±10% RH, 16L:8D photoperiod and 2500 lux light intensity under controlled conditions.The study showed that the preoviposition period significantly shorten when T. urticae and C. pyri were served as prey for 8.44 days and 7.10 days, respectively. The preoviposition period of control group was found as 28.70 days when only E. kuehniella was served as prey. Longevity of females were found 84.89 days and 62.40 days, respectively and total numbers of eggs laid per female were 322.44 and 259.30, respectively, when T. urticae and C. pyri were served as prey for females. Net reproductive rate (Ro) were 304.25 females/female and 220.29 females/female and intrinsic rate of increase (rm) were 0.368 females/female/day and 0.400 females/female/day, respectively