In April 1995, Morioka was selected Japan U-20 national team for 1995 World Youth Championship, but he did not play in the match.
On 31 March 1999, Morioka debuted for Japan national team against Brazil.
After the debut, he became a regular player and played all matches including 1999 Copa America in 1999.
He mainly played as central defender in three back as Masami Ihara successor.
In September 2000, he was elected Japan U-23 national team as over age for 2000 Summer Olympics.
[1] After retirement, Morioka started coaching career at Kyoto Sanga FC in 2009.
However Gainare results were bad and finished at the bottom place of 17 clubs.