Takeshi So (宗猛 Sō Takeshi?, born January 9, 1953 in Usuki, Ōita) is a retired long-distance runner from Japan, who represented his native country at the 1984 Summer Olympics in Los Angeles, California. He won the 1976 edition of the Košice Peace Marathon in Czechoslovakia. His twin brother Shigeru So (宗茂 Sō Shigeru?) is also a retired Olympic marathoner.
He currently trains marathon runner and 2016 Olympics hopeful Satoru Sasaki and runs the marathon program for the Japan Association of Athletics Federations.