Arhopala agesilaus is a species of butterfly belonging to the lycaenid family described by Otto Staudinger in 1889. It is found in Southeast Asia (Thailand, Peninsular Malaya, Langkawi, Mergui, Bangka, Borneo and the Philippines).
Beneath similar to Arhopala kurzi, but of a somewhat lighter ground-colour, with a more coherent postmedian band of the hindwing. Above distinguished by the much broader black margin also in the male, where it is about 3 mm broad.