Abstract In this article, under some weaker assumptions on a > 0 a\gt 0 and f f , the authors aim to study the existence of nontrivial radial solutions and nonexistence of nontrivial solutions for the following Schrödinger-Poisson system with zero mass potential − Δ u + ϕ u = − a ∣ u ∣ p − 2 u + f ( u ) , x ∈ R 3 , − Δ ϕ = u 2 , x ∈ R 3 , \left\{\begin{array}{ll}-\Delta u+\phi u=-a{| u| }^{p-2}u+f\left(u),& x\in {{\mathbb{R}}}^{3},\\ -\Delta \phi ={u}^{2},& x\in {{\mathbb{R}}}^{3},\end{array}\right. where p ∈ 2 , 12 5 p\in \left(2,\frac{12}{5}\right) . In particular, as a corollary for the following system: − Δ u + ϕ u = − ∣ u ∣ p − 2 u + ∣ u ∣ q − 2 u , x ∈ R 3 , − Δ ϕ = u 2 , x ∈ R 3 , \left\{\begin{array}{ll}-\Delta u+\phi u=-{| u| }^{p-2}u+{| u| }^{q-2}u,& x\in {{\mathbb{R}}}^{3},\\ -\Delta \phi ={u}^{2},& x\in {{\mathbb{R}}}^{3},\end{array}\right. a sufficient and necessary condition is obtained on the existence of nontrivial radial solutions.