In this paper, we consider the following problem
-Δu=uN+2/N-2+∈f(x)u, x∈RN,
u∈D1,2(RN), u(x)→0, |x|→∞,
where ∈ is a positive constant, f(x)∈L∞(RN), N>3. Used perturbation method, we prove that under some conditions on f(x), there exists a ∈0, if 0<ε<ε0, such that there are many solutions for above problem.