Oak Grove is an unincorporated community and census-designated place (CDP) in Clackamas County, Oregon, United States.

[5] Oak Grove was named at the suggestion of Edward W. Cornell, a member of the surveying party that platted the townsite in the 1890s.

[6] The company that was developing the property had not been able to come up 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.

[6] Postal authorities did not name the office "Oak Grove" in order to avoid duplication.

Oak Grove is home to a LINCC library operated by Clackamas County.

[8] Oak Grove is located in northwestern Clackamas County, bordered to the north by the city of Milwaukie, to the east by unincorporated Oatfield, to the south by unincorporated Jennings Lodge, and to the west by the Willamette River, whose opposite shore hosts the cities of West Linn and Lake Oswego.

Oregon Route 99E runs through Oak Grove as McLoughlin Boulevard; it leads north 8 miles (13 km) to downtown Portland and south 4 miles (6 km) to Oregon City.