Morgan County is a county located in the U.S. state of Indiana. As of the 2020 United States Census, the population was 71,780. The county seat is Martinsville. Morgan County is between Indianapolis, in Marion County, and Bloomington in Monroe County. It is included in the Indianapolis-Carmel-Anderson, IN Metropolitan Statistical Area. Two major highways, Interstate 69 and Indiana State Road 67, carry large numbers of daily commuters between the two larger communities.