MRHS may refer to:
United States high schools Mount Rainier High School, Des Moines, Washington Mountain Ridge High School (Maryland), Frostburg, Maryland Mountain Ridge High School (Arizona), Glendale, Arizona Mountain Ridge High School (Utah), Herriman, Utah Manchester Regional High School, Haledon, New Jersey Marriotts Ridge High School, Marriottsville, Maryland Minnechaug Regional High School, Wilbraham, Massachusetts Monmouth-Roseville High School, Monmouth, Illinois Mesa Ridge High School, Colorado Springs, Colorado
Other uses Member of the Royal Horticultural Society