West Salem Township Mercer County was formed in 1805 and is located at the West end of Mercer County bordering on the Borough of Greenville. Currently, the Township has a population of 3538 as of the last U.S. Census. Assessed valuation of the land within the Township is $25,864,950 with millage set at 6.

West Salem Township has 46.48 miles of road.

The West Salem Township Board of Supervisors meets the second Tuesday each month at 8:00 a.m. at the township building.