This paper deals with a two-dimensional Keller-Segel-Navier-Stokes system of coral fertilization with porous medium diffusion. When the nonlinear diffusion exponents of sperms and eggs $m>\frac{1}{2}$ , $l>0$ respectively, as well as the strength of fertilization $\mu >0$ , the system possesses a global bounded weak solution. Furthermore, if $0< l<1$ , the corresponding global weak solution stabilizes to the spatially homogeneous equilibrium $(n_{\infty },\rho _{\infty },\rho _{\infty },0)$ in an appropriate sense, where $n_{\infty }:=\frac{1}{|\Omega |}(\int _{\Omega }n_{0}-\int _{\Omega } \rho _{0})_{+}$ and $\rho _{\infty }:=\frac{1}{|\Omega |}(\int _{\Omega }\rho _{0}-\int _{ \Omega }n_{0})_{+}$ .
