Oklahoma is a borough in Westmoreland County, Pennsylvania, United States.

Oklahoma has two land borders, including the townships of Washington to the south and Allegheny to the northwest.

Across the Kiskiminetas River to the east, Oklahoma runs adjacent with the Armstrong County municipalities of (from north to south) North Apollo, Apollo (with a connector via 1st Street Bridge), and Kiskiminetas Township.

At the time of the 2000 census, there were 915 people, 375 households, and 270 families living in the borough.

The racial makeup of the borough was 98.91% White, 0.66% African American, and 0.44% from two or more races.