Abstract: The principal factors influening on the rockfill dams engineering cost estimate in the design stage are the valuation of sandstone materials and balancing earth-rock works allocation. At present， a lot of questions such as the irrationality of the valuation of sandstone materials， the indifference of the balancing earth-rock works allocation， inexactitude compaction quota for earth-rockfill dam materials, and the hiatus in the quota items of the joint water-tight of the concrete face rockfill dams contain in the the compiled investment estimation of rockfill dam engineering， the valuation method of sandstone and the balancing earth-rock works allocation of the details subentry engineering are analyzed accordingly with the quota and practice. And based on the requirement for dam material of the zoning of the rockfill dam， proposing the reasonable combination and the usable range of budget estimate quota of compaction of soil rock in earth-rock dam working operation. And the quota items of joint waterstop of the concrete face rockfill dams are complemented according to the constructed basic structure of dams and the application of the material and construction situations.