Junzo Sekine (関根 潤三, Sekine Junzō, March 15, 1927 – April 9, 2020) was a Japanese professional baseball player who played as two ways as a pitcher and outfielder. He spent the majority of this career with the Kintetsu Pearls/Kintetsu Buffalo/Kintetsu Buffaloes. Sekine was elected to the Japanese Baseball Hall of Fame in 2003. Sekine died on April 9, 2020, in Tokyo, at the age of 93.