The present disclosure provides a discretization modeling method for electro-osmotic drag effect of water conservation in a fuel cell, comprising: establishing a conservation equation of membrane water in the fuel cell, performing a discretization for a complete electro-osmotic drag effect, obtaining a discretization simulation model of the complete electro-osmotic drag effect based on results of the discretization, solving the conservation equation of membrane water to establish a discretization simulation model of electro-osmotic drag effect of water conservation in the fuel cell. The discretization modeling method for the electro-osmotic drag effect of water conservation in a fuel cell in the present disclosure can perform a discretization and a numerical calculation for a complete electro-osmotic drag effect, the discretization comprising a water conservation portion caused by a membrane water content gradient and a water conservation portion caused by a proton transport flux gradient.