Abstract Comparative studies showed no measurable differences among three populations of Propylea quatuordecimpunctata L. (Coleoptera: Coccinellidae) in their developmental and reproductive responses to temperature or photoperiod. Populations of P. quatuordecimpunctata from Canada, France, and Turkey reared on a diet of pea aphids, Acyrthosiphon pisum (Harris), at constant temperatures from 14 to 30°C required approximately 212 degree days (DD) > 10°C to complete preimaginal development. Survival of the three populations generally was highest at 22 and 26°C. On the basis of rearing under five constant-temperature conditions, the Turkish population produced the lowest percentage females (39%), whereas females of the Canadian population constituted the highest percentage (51%). No significant differences were observed among the three populations in the critical photoperiod (ca. L:D 15:9) for diapause induction at 22°C. A comparison of life table parameters, at 26°C, showed that the intrinsic rates of increase ( r m ), total progeny produced, preoviposition period, and net reproductive rates did not differ among the three populations.