In this paper, we study the following nonlinear Schrödinger-Poisson type equation \begin{equation*} -\varepsilon^2\Delta u+V(x)u+K(x)\phi u=f(u), \end{equation*} \begin{equation*} -\varepsilon^2\Delta \phi=K(x)u^2, \end{equation*} where $\varepsilon>0$ is a small parameter, $V: \mathbb{R}^3\rightarrow \mathbb{R}$ is a continuous potential and $K: \mathbb{R}^3\rightarrow \mathbb{R}$ is used to describe the electron charge. Under suitable assumptions on $V(x), K(x)$ and $f$, we prove existence and concentration properties of ground state solutions for $\varepsilon>0$ small. Moreover, we summarize some open problems for the Schrödinger-Poisson system.