The male of Acanthoscurria paulensis Mello-Leitão, 1923 is redescribed and the female is described for the first time. The male holotype, from Pirassununga, state of São Paulo, Brazil, could not be located and the redescription is based on specimens collected in the type locality. Acanthoscurria atrox Vellard, 1924 is considered a junior synonym of A. paulensis based on their original descriptions and figures of the male palpal bulb, and also supported by the study of several specimens from both type localities, Pirassununga and Campo Grande, state of Mato Grosso do Sul, Brazil. Acanthoscurria guaxupe Piza, 1972 is also considered a junior synonym of A. paulensis based on examination of the holotype. Acanthoscurria paulensis resembles A. chacoana Brèthes, 1909, A. juruenicola Mello-Leitão, 1923, and A. geniculata (C.L. Koch, 1842) by the large size (over 50 mm). The male of A. paulensis resembles that of A. chacoana,A. juruenicola, and A. geniculata by the aspect of the palpal bulb with an embolus ending like a shell, due to the well-developed prolateral inferior and superior keels. It can be distinguished from A. chacoana by the palpal bulb less compact and with a longer embolus and from A. juruenicola and A.geniculata by the absence of a third accessory keel. The female resembles A. chacoana,A. juruenicola, and A. geniculata by the fused base of the spermathecae, and differs by the square or slightly wider than longer base of the spermathecae and by the terminal lobes directed towards each other. New distribution records for A. paulensis are provided from the Brazilian states of Mato Grosso, Goiás, Minas Gerais, Mato Grosso do Sul, Espírito Santo, Paraná, and Rio Grande do Sul.