The migration flux is a crucial parameter controlling the migration of hydrocarbon and other fluids in geological media，whereas there is no still unified rate model for describing non-linear flow of hydrocarbon and other fluids in sandbody transport layer with characteristics of typical porous media. Combining with the non-linear dynamics characteristics of hydrocarbon migration，we construct a new migration rate model for calculating the hydrocarbon migration rate in sandbody transport layers based on the main existing rate models of fluids in porous media. Moreover，taking transport layers of Shawan Formation etc. at Chepaizi area in Junggar Basin as an example，this paper illustrates the calculation steps，parameter characterization and resource evaluation application of the new model. The studies show that the hydrocarbon migration rate in sandbody transport layer has very strong non-linear dynamic characteristics. The migration rate，which is the key link between the dynamic mechanism and the migration and accumulation volume in sandbody transport layer，decreases as a power function with increase of the ratio of the resistance gradient to the dynamic gradient. The new model suggests the hydrocarbon migration and accumulation volumes in sandbody transport layers are controlled by the migration rate，the equivalent transport channel，and the charging time. The study provides a new analytical method for hydrocarbon migration analysis and resource potential evaluation in sandbody transport layers.