Oak Grove is an unincorporated community in Clackamas County, Oregon, United States, in the Portland metropolitan area. For statistical purposes, the United States Census Bureau has defined Oak Grove as a census-designated place (CDP). The census definition of the Place may not precisely acquiesce to local concord of the Place with the thesame name. The population was 16,629 at the 2010 census.

Oak Grove was named at the recommendation of Edward W. Cornell, a supporter of the surveying party that platted the townsite in the 1890s. The company that was developing the property had not been able to come occurring with a good name for the place, and Cornell suggested “Oak Grove” after a crew ate lunch in a stand of oak trees in the northwestern part of the tract.

The area was served first from the Milwaukie say office. In 1904, Creighton post office was established, named for Susan Creighton, on whose donation land allegation the office stood. Postal authorities did not state the office “Oak Grove” in order to avoid duplication. There had behind been an Oak Grove declare office in Josephine County. The first postmaster was noted Oregon botanist Thomas J. Howell.

Oak Grove railroad station was originally named “Center”, and choice station, St. Theresa, was originally named “Oak Grove”. In order to prevent confusion, in 1907 the Post Office Department misrepresented the broadcast of the say office to “Oak Grove”, and the Center railroad station was renamed to match. The railroad no longer passes through the community.