Launch Complex 4

Launch Complex 4 may refer to:


 * Cytochrome c oxidase, a component of the electron transport system
 * Cape Canaveral Air Force Station Launch Complex 4, one of the first series of launch complexes to be built at Cape Canaveral Air Force Station, used in the 1950s.
 * Vandenberg Air Force Base Space Launch Complex 4, a launch site at Vandenberg Air Force Base, currently active.