He was born in Osaka in 1905. In 1928, he graduated from Department of Commerce, Kwansei Gakuin University and held a solo exhibition in Osaka Asahi Kaikan.
In 1934, following an advice from Tsuguharu (Leonard) Foujita, he sent his paintings to the Nika-kai and they were selected for the 21st Nika Exhibition.
In 1938, he was involved in organizing the Kyushitsu-kai group with avant-garde artists of the Nika-kai. During the 1930s, Yoshihara’s works were created in a surrealist manner that was popular among Japanese avant-garde artists. Gradually, Yoshihara gains his interest in geometric abstraction.
In 1952, he was involved in forming Gendai Bijutsu Kondan-kai (Genbi) as an organizer. This group served as a workshop and forum for creating new art forms merging Eastern and Western culture as well as the modern and traditional. The main focus of Yoshihara was gaining recognition in the art world through Japanese tradition.
Then in 1954, he organized the Gutai Bijutsu Kyokai (Gutai) and devoted himself to the group as the leader. During this time period, Yoshihara drew inspiration from children’s art, Zen calligraphy, and action painter Jackson Pollock. He held the Gutai Exhibitions from the 1st to the 21st in Japan and abroad.
In 1962, he opened the exhibition space “Gutai Pinacotheca” in Nakanoshima, Osaka. He won the golden award at the Trienniale-India in 1971 and died in Ashiya, Hyogo prefecture in the following year at the age of 67.