AbstractThe first record of the exotic ladybird beetle,Adalia bipunctata(Coleoptera; Coccinellidae), in Japan was in 1993 at Osaka Nanko Central Park. Since that time, studies on the life history and geographical distribution ofA. bipunctatahave been ongoing, and its establishment in the Osaka Nanko area has been confirmed.A. bipunctatais a predacious ladybird beetle and a member of a guild that overlaps in habitat and prey with that of native ladybird beetles such asHarmonia axyridisandMenochilas sexmaculatus. We investigated the distribution ofA. bipunctataand its interspecific relationships with native predacious ladybird beetles. In some areas,A. bipunctatawas dominant in interspecific relationships with native ladybird beetles. For the first 10 years afterA. bipunctatawas discovered, it occurred only in the Osaka Nanko area, but the present geographical distribution indicates that it has expanded its range. Though the population density of this species was highest at the area recorded first, and tended to decrease in inverse proportion to the distance from Osaka Nanko Central Park, a satellite occurrence was observed in a remote area. The numbers of aphid and tree species (leaf shelter for aestivation and over‐wintering) utilized byA. bipunctatahave recently increased. Such increases will cause the rate of distribution ofA. bipunctatato accelerate. Interspecific competition betweenH. axyridisandA. bipunctata, which occurs earlier thanH. axyridis, may be avoided by desynchronization of the occurrence seasons, and another common predacious ladybird beetle,Coccinella septempunctata, may escape interspecific competition by habitat segregation.