Rio Americano High School, colloquially known as Rio, is a public high school in Arden-Arcade, California, just outside Sacramento, serving students in grades 9 through 12 as part of the San Juan Unified School District. Rio Americano students come from the surrounding areas of Arden Park, Arden Oaks, Sierra Oaks, Fair Oaks, Carmichael, Gold River, and to a much lesser extent, the La Sierra community. In recent years, more students have been transferring from other districts and areas, partly due to the shift of Sacramento High School to a charter school. Rio's two rival schools are Jesuit High School and El Camino Fundamental High School because of the schools' close proximity.

As of the 2022–23 school year, the school had an enrollment of 1,884 students. Cliff Kelly is the principal.