By using decomposition method of export margin and HS 6-digit export trade data of 117 countries，this paper decomposes Chinas export growth of 25 manufacturing industries during 2000—2013 into extensive，price and quantity margin.And then the econometric model is put forward and estimated by using system GMM method to empirically explore the impact of financial constraints on export three margins.The results show that Chinas export growth is mainly driven by intensive margin，especially by quantity margin.The ease of internal and external financial constraints can promote the growth of extensive and quantity margin，but play different roles on price margin.The impact of financial constraints on export margins varies among industries of different factor intensity.