This paper focuses on the existence of normalized ground state solution for Schrödinger–Poisson system with doubly critical growth \(\begin{aligned}{\left\{ \begin{array}{ll}\displaystyle -\Delta u-\phi |u|^3u=\lambda u+f\left( u\right) +|u|^4u, & x \in {\mathbb {R}}^{3},\\ -\Delta \phi =|u|^5, & x \in {\mathbb {R}}^{3},~~\end{array}\right. } \end{aligned}\) having prescribed mass \(\begin{aligned} \int _{{\mathbb {R}}^3}|u|^2dx=m^2,\end{aligned}\) where \(m>0\) is a constant, \(\lambda \in {\mathbb {R}}\) is unknown and appears as a Lagrange multiplier, f is a nonlinear term of Sobolev subcritical and is mass supercritical. We show that there exists a normalized ground state solution for the above system when the mass m is large enough. In addition, we also discuss the continuity and monotonicity of the ground state energy \(E_m\) , and explain the asymptotic property of \(E_m\) when m is large enough. Our studies complement and extend the researches of Meng and He (Methods Nonlinear Anal 62:509–534, 2023), in the sense we deal with the effect of mass-changing on the existence of normalized solutions.