To overcome the deficiencies of the material balance method, according to strong heterogeneity of tight oil reservoirs, the flow region of fractured horizontal well is divided into high permeable zone and low permeable zone, which are equivalent to radial composite percolation model. Based on parallel plane theory, multiple media of each zone are equivalent as a continuous medium, and with the integral method, the multi-region material balance to calculate the dynamic reserves for the fractured horizontal w...