This paper focuses on grain production loss caused by Wenchuan Earthquake.The damage of the cultivated area as well as the yield of winter wheat has been assessed.In order to estimate winter wheat acreage damaged by the earthquake

air-borne CCD images and IRS P6 LISS4 MN data were used.Damaged arable land were extracted by photo interpretation

while winter wheat proportions were collected by ground survey using GVG instrument for plain area or interpreted from airborne images for mountain area.The winter wheat acreage damaged by the earthquake was calculated using winter wheat proportion multiple the area of damaged arable land and statistic at county scale.To estimate wheat yield

reliable agro-meteorological models were selected by taking into account the disperse distribution of winter wheat in mountain area.The results showed that only about 247.1hm2 of winter wheat were damaged in the twelve main producing counties and the production loss of winter wheat was estimated to 1013778kg.As conclusion

the earthquake did not significantly affect the food production of the whole country.Nevertheless

since all farmers were evacuated in mountain area after the disaster

the problems of harvest in that region producing 220000t of winter wheat need to be addressed.