Abstract: This experiment was conducted with 21,153 cows and heifers of 3 (three) genetic groups viz. Pabna (PB), PabnaxSahiwal (PBxSL) and PabnaxFriesian (PBxFN) inseminated with frozen semen of Sahiwal (SL), Friesian (FN) and SahiwalxFriesian (SLxFN) bulls to investigate the effects of breeding groups and environmental factors on conception rate (CR). Among the factors considered, it was reflected that parity of dam (p<0.05), time of insemination (P<0.01), season of insemination (p<0.05) and all interactions (p<0.05) had significant effects on CR. The highest CR were found for cows in 0 parity (heifer) (52.11%) or cows inseminated in spring season (51.30%) or inseminated between 8 to 14 hours after onset of estrus (53.24%). The highest CR were also observed in the interaction effects of PBxFN damsxSL sires (52.75%) or SL siresxspring season (52.17%) or PBxFN damsxwinter season (52.21%) or cows inseminated within 8 to 14 hours after the onset of estrusxspring season (54.55%)-indicating that combination of inseminating dams in right time of estrus using appropriate sire in appropriate season would contribute greatly to improve the status of CR in PB and its crossbred with SL and FN cows of Bangladesh.