1967年京都府舞鶴市生まれ。1989年文化出版局写真部入社。自身の作品制作を行いながら、ファッション写真・広告写真・CDジャケット、ムービー、ドローン撮影などを手がけている。
Through rhythmic repetition and seriality, Osamu Yokonami explores identity and cultural homogeneity. His twin series, 1000 Children 2010-2013 and Assembly on-going since 2010 explore conceptions of selfhood and the range of human emotions, suggesting a reflexive and essential congruence between individual expression and communal belonging. A related series, Assembly Snow 2015, is an extension of the original where the forces of nature and culture blur into abstraction. More recently, Osamu has undertaken a new project, After 1000 Children 2017-2018, locating girls from the initial series for side-by-side comparisons of them alongside their younger selves.