AbstractKanazawa Castle Park (KCP) is an isolated urban green area in Kanazawa, Japan. A mature forest had developed there since 1949, but it was partially deforested from 1996 to 1999. Moreover, most of the grasslands in KCP were removed from 2000 to 2002. In this study, we report the damage to the butterfly assemblage by these anthropogenic disturbances and subsequent recovery after the disturbances, using previous literature on the butterfly assemblage in KCP from 1990 to 1994 and our monitoring data from 1999 to 2005. In addition, to understand urbanization effects, we also compared the butterfly assemblage of KCP with that of Tawara, a satoyama area 6 km away from KCP. Before the urbanization around KCP, KCP might have had a butterfly assemblage similar to Tawara. The previous articles indicate that 33 species lived in KCP before the partial deforestation. The number of generalist species (multivoltine and polyphagous species) was similar in KCP and Tawara (22 vs. 19), but that of specialist species (uni‐bivoltine and oligophagous species) was lower in KCP than in Tawara (5 vs. 15). Six species, composed of a bamboo grass feeder, mantle feeders, herb/grass feeders, and a multi‐feeder, disappeared from KCP after the deforestation and have not yet recolonized. The grassland removal also affected herb/grass feeders negatively, but they have been recovering quickly following the partial grassland recovery. Some species that disappeared after the deforestation were sporadically found from 2000 to 2005 probably due to immigration from the surrounding rural areas (the nearest one is 2 km away). For recolonization of the lost species, recovery of the interior and edge of the forest, which are the habitats for these species, is necessary.