Abstract: In this paper，it conducts the three-dimensional simulation calculation on the earth and rockfill dam of Ertanggou hydro-project in Sinkiang Turpan based on the finite element method，and analyzes the stress-strain extreme values of rockfill body and core-wall after the completion period and full storage period.The result shows that the design of the earth and rockfill dam is reasonable，the rockfill body and core-wall won’t appear tension-compression damage and shear failure.At the bottom of the core-wall，it appears about 7cm slight inflation towards to both sides and which makes it become the dangerous place.So we should pay more attention to the design and construction process.