Marietta High School (MHS) is a four-year, public, secondary school in Marietta, Ohio, United States. The school serves students in the Marietta City School District in grades nine through twelve. As of 2010–2011, the approximate enrollment was 1,050. Marietta's mascot is Tabby the tiger and its colors are orange and black. The school participates in both the Ohio Valley Athletic Conference and Twin State League. MHS is accredited by the North Central Association of Colleges and Secondary Schools and the Ohio Department of Education.