Watertown High School (WHS) is the local high school, built in 1925, for Watertown, Massachusetts, United States. The school is home to the Watertown Raiders, who are best known for their varsity field hockey and boys' basketball programs. Watertown's colors are black and red. The school newspaper is the Raider Times. On May 8, 1930, ex-President Calvin Coolidge was received at the school as town celebrated its 300th anniversary. As a part of the celebration, a national radio program was broadcast from the high school marking the momentous anniversary.

The demolition of the old Watertown High School building began on November 13, 2023. With the construction scheduled to finish in time for the 2026 school year.

The new Watertown Highschool total project budget as provided by the district is $201,461,673.