Ruutu played for HIFK and Jokerit in the FinnishSM-liiga, earning a silver medal with HIFK and the SM-liiga championship with Jokerit in 2002. He was drafted by the Ottawa Senators as their 7th round pick in the 1999 NHL Entry Draft, but his only season in North America was for Clarkson University in the NCAA league. He has since retired from professional hockey because of his broken knee. He is currently a scout for the Ottawa Senators.
Mikko Ruutu has two brothers, Jarkko, a former NHL player who retired in 2014, and Tuomo, who plays in the NHL for the New Jersey Devils.