In this paper, we study the following Schrödinger-Poisson equations − Δ u + u + ϕ u = u 5 + λ a x u p − 1 u , x ∈ ℝ 3 , − Δ ϕ = u 2 , x ∈ ℝ 3 , where the parameter λ > 0 and p ∈ 0 , 1 . When the parameter λ is small and the weight function a x fulfills some appropriate conditions, we admit the Schrödinger-Poisson equations possess infinitely many negative energy solutions by using a truncation technology and applying the usual Krasnoselskii genus theory. In addition, a byproduct is that the set of solutions is compact.