O'Fallon Park is a municipal park in St. Louis, Missouri, that opened in 1908.

Under Alderman John Collins-Muhammad the park underwent a million dollar remodeling including renovations on the historic O'Fallon Park Boathouse. The work is part of a three-year project including upgrades to park infrastructure and a fresh coat of paint.

The park is named after John O'Fallon, a colonel who fought in the War of 1812 and nephew of William Clark. The park is 126.63 acres and was once part of O'Fallon's 600-acre land holding. The park has a lake with a boathouse. It has basketball courts, tennis courts, softball fields, and a football field. It has a playground, multiple picnic grounds, and a spray pool.

O'Fallon Park is located near the riverfront. On the north, it is bordered by Interstate 70; on the southwest, by W. Florissant Ave. The southeastern border follows E. Harris Ave., Algernon St., and Adelaide Ave.

O'Fallon Park is surrounded by five St. Louis neighborhoods. North Riverfront borders the north, Penrose borders the west, Near North Riverfront borders the east by a tip, and finally two neighborhoods border the south, O'Fallon and College Hill.

• John O'Fallon
• People and culture of St. Louis, Missouri
• Neighborhoods of St. Louis
• Parks in St. Louis, Missouri

• O'Fallon Park - Official St. Louis Park Department website