Born in Saitama Prefecture on September 12, 1942. Entered Tama Art University Department of Oil Paining in 1962 and continued his education in the same graduate program where he studied under Saito Yoshishige (graduated in 1968). Achieved many awards including those for "Phase No. 6" at the 8th Gendai Bijutsuten in 1968; for "Phase - Mother Earth" at the Open Air Contemporary Sculpture Exhibit at Suma Rikyu Park; for "Phase - Sponge" at the 5th Nagaoka Museum of Modern Art Exhibition; and others. Exhibited "Phase of Nothingness" at the 35th Venice Biennale in 1970. He used this opportunity to travel through Europe, and returned in Japan in 1971.

Established the Envionmental Art Studio in 1973 (closed in 2010). In 1977, the Louisiana Museum in Denmark completed their permanent Sekine Corner. 1978, a Sekine exhibition traveled around Europe, including at the Louisiana Museum. Sekine moved to Shanghai in 2010. He moved again to the Palos Verdes peninsula in southern Los Angeles in 2012, where he continued his work. Passed away at age 76 on May 13, 2019 at a hospital in Torrance, just outside Los Angeles.