Abstract: In order to solve the problem of unsteady fluid flow infractured rock, a new numerical model is proposed. For the calculation offluid flow in a single fracture, the governing equations are simplifiedNavier-Stokes equations based on some assumptions, which arenumerically solved by the finite difference method and the volume of fluid method. In afracture network, the fluid flow in intersection places is governedby special equations. The results show that this numerical model could notonly improve the computational efficiency of unsteady fluid flow in thefractured rock, but also avoid the influence of isolated fractures. Finally,the applicability of the numerical model is validated by two engineeringexamples.