For other places with similar names, see Morristown, New Jersey (disambiguation).

Morris Plains is a borough in Morris County, New Jersey, United States. As of the 2010 United States Census, the borough's population was 5,532, reflecting an increase of 296 (+5.7%) from the 5,236 counted in the 2000 Census, which had in turn increased by 17 (+0.3%) from the 5,219 counted in the 1990 Census.