Lake is a second-class township in Wayne County, Pennsylvania, United States.

The township's population was 5,269 at the time of the 2010 United States Census.

There were 4,009 housing units at an average density of 144.2 per square mile (55.7/km2).

There were 2,156 households, out of which 21% had children under the age of 18 living with them, 58.7% were married couples living together, 7.9% had a female householder with no husband present, and 29.9% were non-families.

24.4% of all households were made up of individuals, and 10.6% had someone living alone who was 65 years of age or older.