The goal of the present study was to evaluate effect of social status and genotype on success of reproduction of male laboratory mice with use of ethological model of social hierarchy of "minimal socium". The model represents the paired maintenance of two male mice of different genotype (PT and CBA/Lac). The mice lived for 30 days in one experimental cage males, two females of the DD/He strain were supplemented. Regardless of genotype, the dominants became fathers more often than the subordinants and got more progeny. It was established that in subordinates there did not occur the complete suppression of fertility. This is suggested to allow them to realize the genetical contribution to the next generation and to remain in the gene pool of population.