The KJ-1 (from Chinese: 空警; pinyin: Kōng Jǐng, short for 空中预警 kōngzhōng yùjǐng meaning "airborne early warning") was a Chinese experimental airborne early warning (AEW) aircraft, based on a Tupolev Tu-4 bomber aircraft (itself being an unlicensed, reverse engineered copy of the Boeing B-29 Superfortress[1]).

The KJ-1 was the first-generation AEW aircraft developed by the People's Republic of China.

According to Chinese government claims, a single KJ-1 would have functions equivalent to more than 40 ground radar stations, but the test flight in the early 70s experienced severe mid-flight vibrations that could not be solved, and the development was stopped later amongst the political chaos of the Cultural Revolution.

The only KJ-1 aircraft built was dismantled after the project was scrapped, and the KJ-1 now on display at the China Aviation Museum in Beijing is actually a reconstructed replica converted using another Tu-4.

[2][citation needed] In the KJ-1's place, PRC developed a phased-array radar for its KJ-2000 AWACS aircraft, based on a modified Ilyushin Il-76 airframe.