Munemasa Kobayashi majored in photography at Nihon University and graduated in 1968. After working at various advertising companies such as the Japan Design Center and Tokyu Agency Inc. he began working independently in 1975. In 1987, he established Mune Studio Inc. where he currently works.
His works have been nominated for the Asahi Advertisement Award in 1973 as well as the Asahi and Mainichi Advertisement Awards in 1974. In 2001 he was nominated for the 48th Catalogue & Poste Fair Advertisement Award. He acquired Color Management Professional degree in 2009, and was assigned to the Denjuku headquarters steering committee in 2011.
Currently he photographs still life, fashion, people, and numerous other motifs. His creative use of light in his vivid depictions of still life is of particular interest.