Oklahoma's 5th congressional district is a congressional district in the U.S. state of Oklahoma. It borders all of the other congressional districts in the state except the 1st district. It is densely populated and covers most of Oklahoma County and all of Lincoln, Pottawatomie and Seminole counties, as well as parts of Canadian and Logan counties. With a Cook Partisan Voting Index rating of R+12, it is the least Republican district in Oklahoma, a state with an all-Republican congressional delegation.

Oklahoma County is located in the central part of the U.S. state of Oklahoma. As of the 2020 census, the population was 796,292, making it the most populous county in Oklahoma. The county seat is Oklahoma City, the state capital and largest city. Oklahoma County is at the heart of the Oklahoma City metropolitan statistical area.