Abstract: This paper systematically introduces the application of horizontal well in domestic and abroad.The technology of horizontal well is mainly used in follows oil (gas) reservoirs,such as thin oil reservoir,naturally fractured reservoir,oil reservoirs with gas coning and water coning,gas reservoirs with bottom water coning.The horizontal well has become more and more important to produce heavy oil,water driving and other EOR reservoirs.The status of horizontal well and complex-structure well production technology were analyzed in details,including artificial lift manners、stimulation measures、sand-prevention and sand controlling technology,water-finding and water plugging technology etc.The problems urgently to be studied for production technologies of horizontal well and complex-structure well were also prospected.