Prior experience often affects behaviors and outcomes of subsequent contests. Although the effects of prior contest experience have been widely examined, effects of mating experience remain less well examined. We examined, in males of the hermit crab Pagurus nigrofascia, whether males successively copulated with females, and whether males with copulation experience differed their subsequent contest behaviors and probability of winning in male-male contests from males without copulation experience. The copulation experience of intruders was manipulated and the contest behaviors compared between mated and unmated groups. Males mated with several females regardless of the male body size. Compared with unmated intruders, intruders with mating experience succeeded more often to takeover females within a shorter period when the male-male contests occurred over females with a longer time to molt. These results suggest that mated males of P. nigrofascia might overestimate the female quality and/or enhance the competitive performance similar to the ‘winner effect’ that is a positive feedback from prior winning experience to future contest.