Harrisville is a borough in Butler County, Pennsylvania, United States.

Col. Robert Reed built a tavern and a distillery just south of present-day Harrisville in 1797.

Harrisville is located near the northwestern border of Butler County at 41°8′6″N 80°0′35″W / 41.13500°N 80.00972°W / 41.13500; -80.00972 (41.134966, −80.009590).

Harrisville is drained by McMurray Run, a tributary of Slippery Rock Creek.

There were 346 housing units at an average density of 423.0 per square mile (163.3/km2).

24.5% of all households were made up of individuals, and 9.3% had someone living alone who was 65 years of age or older.