Martin Luther King Jr. High School is a public high school located in unincorporated DeKalb County, Georgia, United States, with a Lithonia postal address. It opened in August 2001 as the newest high school in the DeKalb County School System, and was named after the late civil rights leader Martin Luther King Jr.
Its boundary includes a portion of Stonecrest.
The school was opened to alleviate overcrowding in surrounding middle schools. It originally included only grades 6-7 and 9-10. Tenth grade students came from Cedar Grove, Lithonia ,and Southwest DeKalb High Schools to relieve crowding and also due to the rezoning of DeKalb County. The following year, after a protest by the high school students, the school dropped the sixth and seventh graders and added eighth grade. It became a pure high school with grades 9-12 in the 2003-2004 school year.
MLK's current principal is Harvey.
Salem Middle School is the middle school feeder to MLK.
MLK implemented the International Baccalaureate Diploma program during the 2004-2005 school year.