The road turns to the east-southeast and continues through more rural areas, crossing the North Fork Little Beaver Creek and reaching an intersection with PA 551.

The road passes over Norfolk Southern's Fort Wayne Line and turns to the south, heading into wooded areas with some homes.

[2][3] PA 351 enters Darlington Township in Beaver County and becomes Crescent Drive, turning southeast into a mix of farmland and woodland with some homes.

The road turns south near more fields and heads into the borough of New Galilee, becoming Cleveland Drive and curving southwest past homes.

At this intersection, PA 351 crosses into the borough of Koppel and becomes Arthur Street, passing residences and businesses.

The route crosses Norfolk Southern's Koppel Secondary railroad line and turns north onto 5th Avenue, heading past more development.

Past the bridge, the route turns north onto River Road and heads through wooded areas with some commercial development.

The road heads into the borough of Ellwood City and turns to the east, becoming Lawrence Avenue and passing through business areas.