Allegany High School is a public high school in Cumberland, Maryland, United States. It is part of Allegany County Public Schools. Allegany High School was built as Allegany County High School in 1887, hence it is often referred to as 'Alco'.

As of the 2014–2015 school year, the school had an enrollment of 671 students and 43.3 classroom teachers (on an FTE basis), for a student–teacher ratio of 15.5:1. There were 252 students (37.6% of enrollment) eligible for free lunch and 30 (4.5% of students) eligible for reduced-cost lunch. Students were 93% white, 5% African-American and 2% Asian. Allegany High School's most historic and well-known rivalry is with Fort Hill High School, a long-standing and passionate football rivalry that began in 1936.