The invention provides a method for suppressing frequency dispersion in orthogonal medium seismic wave field simulation, which comprises the following steps of: 1, converting crack physical parameters into orthotropic medium parameters by using a rock physics theory and a crack equivalent theory, and providing a model for orthogonal medium forward modeling; 2, deriving an orthogonal medium elastic wave first-order velocity-stress equation according to a seismic wave dynamics theory combining a crack medium rigidity matrix; 3, solving the orthogonal medium elastic wave equation by using a finite difference method and modeling a propagation process of seismic waves in crack mediums; 4, optimizing an orthogonal medium staggered mesh difference coefficient by using a least squares optimization method, thereby suppressing the frequency dispersion and improving the modeling precision; and 5, performing a modeling test. The method for suppressing the frequency dispersion in the orthogonal medium seismic wave field modeling derives the differential coefficient which can obtain high precision simulation results in a larger frequency region, and can be used to suppress the frequency dispersion. When a model speed is low or a main frequency of a seismic subwave is high, the effect is more obvious.