Pittsfield Township is a township in Warren County, Pennsylvania, United States. The population was 1,519 at the 2000 census.According to the United States Census Bureau, the township has a total area of 55.6 square miles, all of it land.As of the census of 2000, there were 1,519 people, 594 households, and 453 families residing in the township. The population density was 27.3 people per square mile. There were 766 housing units at an average density of 13.8/sq mi. The racial makeup of the township was 99.74% White, 0.13% Native American, and 0.13% from two or more races. Hispanic or Latino of any race were 0.13% of the population.There were 594 households out of which 35.9% had children under the age of 18 living with them, 64.1% were married couples living together, 6.9% had a female householder with no husband present, and 23.7% were non-families. 21.2% of all households were made up of individuals and 7.9% had someone living alone who was 65 years of age or older.