In 1996, after graduating from Kyoto Gakuen High School, Miki entered Ryukoku University, where he would play the All-Japan University Rugby Championship.

He also took part at the 1999 Rugby World Cup,[3] but did not play any match in the tournament.

In 2000, Miki graduated from Ryukoku University and joined the Toyota Motors club.

In 2004, he moved to World Fighting Bull in the Top League and ended his international career after a disastrous European tour in 2004,[5] in the match against Wales, at the Millennium Stadium, on 26 November.

[8] Miki retired as player in 2011 after playing the season for Panasonic Wild Knights.