Sector 4 is one of the major sectors in the city of New Mombasa, Kenya, Earth. It is located beside Sector 3 and Sector 10, in the Kizingo district. Kizingo Boulevard is also partially located within this sector.
- In the hub level of Halo 3: ODST, the beacon to trigger Mickey's Flashback level can be found here.
- In a courtyard towards the middle of the city, there is a crashed SOEIV, presumably Romeo's.