Miyase was born in Chiba Prefecture and would join the Japan Golf Tour after turning professional.

He won his first title on the Japan Golf Tour in 1997 and would add six more wins between then and 2007.

[2] In 2004, Miyase played on the PGA Tour in the United States after finishing T28 at qualifying school.

[3] Japan Golf Tour playoff record (4–2) CUT = missed the half-way cut "T" = tied Note: Miyase only played in The Open Championship.

1Cancelled due to 9/11 QF, R16, R32, R64 = Round in which player lost in match play NT = No tournament