Roxbury High School is a four-year comprehensive public high school in the Succasunna section of Roxbury in Morris County, New Jersey, United States, serving students in ninth grade through twelfth grades, operating as the lone secondary school of the Roxbury School District, which serves more than 3,500 students. The school serves students from Roxbury, as well as from Mount Arlington, who attend as part of a sending/receiving relationship with the Mount Arlington School District.