The seismic forward modeling of the Leikoupo reef-band reservoirs of the Middle Triassic in Xiaoquan-Xinchang-Hexinchang gas field(XXH area) in western Sichuan Basin is presented,based on which the seismic response model for such reservoirs is developed.By the seismic attribute optimization,it is suggested that the seismic reflection intensity and energy frequency scanning are helpful to the lithology characterization.The regional distribution of gypsum salt,drilling data,bank-body geologic model forward analysis,seismic reflection and seismic velocity are compared with those from Puguang gas field,indicating the seismic prediction of reef-bank reservoirs is reliable.Also,this paper points out four favorable areas of such a reservoir development extending in SW-NE in zonality.