Olean is a city in Cattaraugus County, New York, United States. Olean is the largest city in Cattaraugus County and serves as its financial, business, transportation and entertainment center. It is one of the principal cities of the Southern Tier region of Western New York.

Cattaraugus County is a county in Western New York, with one side bordering Pennsylvania. As of the United States 2020 census, the population was 77,042. The county seat is Little Valley. The county was created in 1808 and later organized in 1817. The county is part of the Western New York region of the state.