Monmouth-Roseville High School, or MRHS, is a public four-year high school located at 200 South B Street in Monmouth, Illinois, a city of Warren County, Illinois, in the Midwestern United States.

[2] The campus is located in Monmouth, IL, 17 miles west of Galesburg, Illinois, and serves a mixed city, village, and rural residential community.

The school is in the Galesburg micropolitan statistical area which includes all of Knox and Warren counties.

[4] In 2009 the faculty was 122 teachers, averaging 16.0 years of experience, and of whom 24% held an advanced degree.

[6] The faculty in 2019 was 121 teachers, the average class size was 17.7, and the school's instructional spending per student was $5,946.