Bombers are aircraft used to bomb forward areas, strategic rear areas and targets at sea. According to their weights, bomb loads and ranges, they can be divided into light bombers (or short range bombers), medium bombers (or medium range bombers) and heavy bombers (or long range bombers). They can also be divided into strategic bombers and tactical bombers according to their operational missions.

The bombers were first used in the First World War. Most of them were retrofitted from reconnaissance aircraft and could carry a small amount of bomb loads. The bombers were widely used during the World War II. The four?engine heavy bombers also appeared at that time. The high subsonic jet bombers were developed in 1950s and the supersonic medium range strategic bombers in 1960s . During 1970s the USA and the Soviet Union developed strategic bombers with speed higher than Mach number 2. These supersonic strategic bombers could penetrate into enemy's territorial air in supersonic speed at high altitude or in high subsonic speed at very low altitude.

A policy of active defence was adopted by China in its national air defence so that the light bombers and medium bombers have also been developed while the stress of the aircraft development was placed on the fighters.

After 1950s the Chinese aviation industry planned to develop the bombers step by step. Two enterprises for development and production of bombers (also transports and helicopters) and two design institutes for design of land based and water based bombers were respectively established and the corresponding infrastructure was constructed. The H-5 light bomber and the H-6 medium bomber with its derivatives were produced and the water?based SH-5 was developed on our own. Through all these activities a technical team of bomber development was tempered and a moderate production capacity formed. China had then basically the ability to develop light and medium bombers.