Composite material combines two or more materials into one combined material to get the desired characteristics of each material. Functionally Graded Material (FGM) is a type of composite material that combines two materials in the form of gradation of materials that is being developed as an alternative to the conventional composite material. To support this material, numerical simulation by the Finite Element Method (FEM) is very interesting. In this paper, the Discrete Shear Beam Element (DSB) element is used to evaluate the effect of the shear correction factor in FGM beam structures. In much of the literature, the shear correction factor is assumed to be constant. This assumption is correct for isotropic structures, but in FGM structures, this factor is not constant. A simply supported beam with various boundary conditions and thickness length ratio is evaluated to understand the effect of this factor. The results show that by using the true shear correction factor, the results will be close to the reference solution. Moreover, for the FGM beam with the significant ratio of modulus elasticity, the use of the true shear correction factor is a must to get a solution as close as possible to the reference solution. © 2024 Author(s).