Sherman County is one of the 36 counties in the U.S. state of Oregon. As of the 2020 census, the population was 1,870, making it the second-least populous county in Oregon after nearby Wheeler. The county seat is Moro, and the largest city is Wasco. The county is named for William Tecumseh Sherman, a Union general in the American Civil War.

Wasco is a city in Sherman County, Oregon, United States. The population was 410 at the 2010 census.