Grinnell College is a four-year undergraduate liberal arts college located in Grinnell, Iowa. The college, originally known as Iowa College, was the first college to be founded west of the Mississippi River. It was founded on June 10, 1846, when a group of transplanted New England Congregationalists with strong social-reformer backgrounds organized themselves as the Trustees of Iowa College.

Grinnell College has consistently been named among the top 20 liberal arts colleges by the magazine U.S. News & World Report during the past fifteen years.

Iowa College moved from Davenport, Iowa to the town of Grinnell in the mid-19th century, after difficulties with residents in Davenport forced the college to relocate. The college moved to Grinnell after being invited by Josiah Bushnell Grinnell (to whom Horace Greeley purportedly gave his famous advice, "Go West, young man") to move to his newly-founded town, located at the intersection of two major railway lines. Today, one can still experience the effects from this choice of location in the form of a railroad that cuts across the college campus.

In 1909 the name Grinnell College was adopted by the trustees as the college name.

Famous attendees of Grinnell College include Robert Noyce, co-founder of Intel Corp.; Attorney Joseph Welch, who defended the Army against Senator Joseph McCarthy; Olympic champion Morgan Taylor; jazz great Herbie Hancock; movie star Gary Cooper; Nobel Prize winner Thomas R. Cech; WPA administrator Harry Hopkins; Walter Koenig, (Star Trek's Pavel Chekov); author James Norman Hall; and South Sudanese rebel leader John Garang de Mabior.

The school's sports teams are the Pioneers. They participate in the NCAA's Division III and in the Midwest Conference.

Grinnell College is one of several liberal arts colleges that have an active campus-wide blogosphere community. The system used at Grinnell is an unofficial service known as GrinnellPlans. Membership is limited to students, faculty, and alumni.