We investigate normalized solutions of the following Choquard equation perturbed by saturable nonlinearity \(\begin{aligned} \left\{ \begin{array}{ll} -\Delta u+\lambda u=\left( I_{\alpha }*|u|^{p}\right) |u|^{p-2}u+\mu \frac{g(x)+u^{2}}{1+g(x)+u^{2}}u\ \ & \text { in}\ \mathbb {R}^{N}, \\ \int _{\mathbb {R}^{N}}u^{2}dx=c>0, & \end{array} \right. \end{aligned}\) where \(2_{\alpha }:=\frac{N+\alpha }{N}\le p\le 2_{\alpha }^{*}:=\frac{N+\alpha }{N-2}\) , \(\mu \in \mathbb {R}\backslash \{0\},\) and g(x) is a bounded intensity function on \(\mathbb {R}^{N}\) . Under different assumptions on \(p,\mu \) and g(x), we prove several existence and nonexistence results. We also describe some properties on the associated Lagrange multipliers \(\lambda ,\) including the asymptotic behavior as \(c\rightarrow 0\) and the relationship with the distribution potential g(x).
