Yun was born in Korea in 1922 into what is believed must have been an affluent family, since he (like other kwan founders) was sent abroad for his education during the Japanese occupation of Korea. Unlike many of the early kwan founders who studied Shotokan karate under Gichin Funakoshi, Yun did not. Yun actually started studying karate while attending secondary school in Osaka with Kenwa Mabuni. Mabuni was an Okinawan living in Japan teaching his brand of Karate which he called Shito Ryu. Yun then attended Nihon University where he studied Shudokan karate under Toyama Kanken. Yun also trained in Chuan Fa in Manchuria. Upon his return to Korea, Yun began to teach in Sang Sap Chun's school, Yun Moo Kwan, the school that eventually became Jidokwan.
After Master Chun disapeared during Korean War, the original students of Chun voted Yon as Jidokwan president. According to some sources, in the mid 1960s Yon opposed the kwan unification being advocated by the Korea Taekwondo Association (KTA) and was voted out of Jidokwan; other sources highlight Yon's support for the KTA. In either case, Chong Woo Lee then became the 2nd Jidokwan President.