The present work was carried out to study the effect of four introduction cycles (February, March, April, May) of F1 Carniolan and F1 Italian virgin queens introduced on 3-and 5comb mating nuclei of the same and inverse subspecies (genotype) on virgin acceptance and mating success. The experiments were made in a private apiary located at Zagazig District, Sharkia Governorate, Egypt during 2016 and 2017 seasons. Results revealed that virgin acceptance rates for both F1 Carniolan and F1 Italian virgins were relatively higher in February and March introduction cycles, recording between 90.0-100.0% acceptances in the two seasons. The least acceptance rates were exhibited in April introduction cycle for both hybrids, meanwhile the least mating success was recorded for May cycle in the two seasons. The rate of acceptance was relatively similar in both 3-and 5-comb mating nuclei. Meanwhile, mating success of virgins of both subspecies was relatively higher in the stronger mating nuclei (5-comb nuclei). Introducing virgin queens in mating nuclei of the inverse genotype, showed varied acceptance and mating success values between the two virgin genotypes, where F1 Carniolan virgin queens introduced on 5-comb F1 Italian mating nuclei showed means of 77.5 and 80.0% acceptances, meanwhile F1 Italian virgins introduced on 5-comb F1 Carniolan mating nuclei recorded means of 82.5 and 85.0% acceptances when introduced on F1 Carniolan mating nuclei in the two seasons, respectively. In addition, mean mating success rate was relatively higher for F1 Italian queens introduced on 5-comb F1 Carniolan mating nuclei that recorded 96.88 and 94.10% compared to 85.07 and 84.28% for F1 Carniolan queens mated in F1 Italian nuclei in both seasons, respectively.