Parapatric distributions of closely related species are common in many taxonomic groups. However, habitat overlap in sympatric areas within both species' ranges is complex and driven by the nature of the interactions between species as well as each species' ecological requirements. We therefore investigated the distribution of breeding habitats for two congeneric frogs,Pelophylax nigromaculatusandPelophylax porosus brevipodus, in a region of Japan where these species co-occur, based on observation of mating calls as an index of the abundance of males engaging in reproductive activities. Among a total of 381 surveyed sites,P. nigromaculatusandP. porosus brevipoduswere found at 171 and 229 sites, respectively.Pelophylax porosus brevipoduswas widely distributed throughout the study area and was more abundant thanP. nigromaculatusin sympatric sites. Analysis using cumulative link mixed models revealed that the abundance of calling males was negatively affected by the presence of calling males of the other species and by landscape factors. Interspecific differences in this negative effect appear to favorP. porosus brevipodusoverP. nigromaculatusin our study area. Due to differences in the primary habitat preferences of the two species during the non-breeding season, habitat partitioning during the breeding season is likely driven by negative interspecific interactions during the reproductive process (i.e., reproductive interference).