This essay reads Tanizaki Jun'ichiro's controversial novel Diary of a Mad Old Man (1961) for its contribution to discourses about aging masculinity and male sexuality in later life. The Diary meditates on the mental and physical vicissitudes of aging masculinity, arousal, control, and impotence, focused through the fictional diarist Utsugi's physical ailments and expression of libidinal intensities. The article argues for Tanizaki's depiction of male aging as an exercise in both disenfranchise-ment and agentive potential. First, it reads the aging process through aesthetic and visual strategies, which magnify the protagonist's cultivation of masochistic plea-sure as a specific correlative of aging. The article demonstrates that the narrative uses the rhetoric of cinema and photography - central terms of reference in Taniza-ki's work - to frame Utsugi's experiences of old age, and inform his erotic fantasies as stylized, staged performances. In conjunction with these visual modes, the novel draws on traditional Japanese aesthetics to conceptualize the potential affect and perverse empowerment of the aging experience. Second, it addresses the implica-tions of narrative form, as the self-reflexive, first-person diary prioritizes the subjec-tivity of Utsugi's male old age, while the novel's final pages interrupt and thus alter the diary's significance as a private account of self-expression.