In this paper, we consider the following fractional Schrödinger–Poisson system with singularity
\begin{equation*}
\left \{\begin{array}{lcl}
({-}\Delta)^s u+V(x)u+\lambda \phi u = f(x)u^{-\gamma}, &&\quad
x\in\mathbb{R}^3,\\
({-}\Delta)^t \phi = u^2, &&\quad x\in\mathbb{R}^3,\\
u>0,&&\quad x\in\mathbb{R}^3,
\end{array}\right.
\end{equation*}
where 0 < γ < 1, λ > 0 and 0 < s ≤ t < 1 with 4s + 2t > 3. Under certain assumptions on V and f, we show the existence, uniqueness, and monotonicity of positive solution uλ using the variational method. We also give a convergence property of uλ as λ → 0, when λ is regarded as a positive parameter.