Martinstown is a townland in County Westmeath, Ireland. It is located about north of Mullingar.
Martinstown is one of 11 townlands of the civil parish of Stonehall in the barony of Corkaree in the Province of Leinster. The townland covers .
The neighbouring townlands are: Knockbody to the north, Farrancallin and Taghmon to the east, Sheefin to the southâÂÂeast, Parsonstown to the south, Galmoylestown Upper to the southâÂÂwest and Blackmiles to the northâÂÂwest.
In the 1911 census of Ireland, there were 11 houses and 57 inhabitants in the townland.