The Iowa Mountain Bike Championship Series (IMBCS) is a series of cross-country mountain bike races held throughout Iowa and nearby in bordering states.

Each individual event has its own race director and offers its own awards. The series has a point system in place to award competitors at the end of the season in their respective race categories. This allows riders to travel around the state and compete at different venues while earning points toward a series championship.

Each race, and the series as a whole, offers different levels of competition. There are beginner (Cat 3) races for those who are looking for fun or are just new to the sport. Cat 2 Sport and Cat 2 Comp races provide an opportunity for those looking to move up to new challenges, and Cat 1 Expert races allow riders to test themselves against the best. Some venues offer Marathon class races for those who are looking to go long. Kids races encourage the next generation.