Union Hill High School was a public high school serving students in grades 9–12 from Union City in Hudson County, in the U.S. state of New Jersey, operating as one of two high schools of the Union City Board of Education, an Abbott District. The school was built in—and named for—what was formerly Union Hill, a municipality which merged with West Hoboken in 1925 to form Union City. Until 2008, Union Hill was one of the city's two high schools, with the former Emerson High School the other. The Union Hill and Emerson campuses continued to serve high school students for an additional year as separate campuses of the new Union City High School, after which that school's main campus was completed and both schools were converted to their current designation. The building that housed Union Hill High School is now Union Hill Middle School and houses students in grades seven and eight.