Mashpee is a town in Barnstable County, Massachusetts, United States. The population was 12,946 at the 2000 census. For geographic and demographic information on specific parts of the town of Mashpee, please see the articles on Mashpee Neck, Monomoscoy Island, New Seabury, Popponesset, Popponesset Island, Seabrook and Seconsett Island.