New York State Route 242 (NY 242) is a state highway that runs across Cattaraugus County, New York, in the United States. Although signed as an east–west route, it takes a more northeast–southwest course across the county from NY 394 near the hamlet of Randolph in the town of Coldspring to NY 16 in Machias. The western end between Randolph and Little Valley was the western half of the short-lived New York State Route 17H. The eastern half of NY 17H was the southern end of NY 353 from Little Valley to Salamanca.

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.