Abstract: It is very difficult to get the analytic expressio n of limit state equ ation in the reliability analysis of complicated and non-linear structures suc h as concrete faced rockfill dam (CFRD).Response surface method ( R SM) is applied in analyzing the reliability of the concrete f ace slab in CFRD for the first time. CFRD is calculated by 3-D non-linear FEM and the reliability analysis of the concrete face slab in CFRD i s calculated by two-order RSM. The calculated results of an example of CFRD co nf irm the superiority in the precision and efficiency of RSM solving the reliabili ty analysis of complicated structure such as CFRD.