In this paper, the natural frequencies of functionally graded porous (FGP) beam are determined associated with two kinds of porosity. The simple beam theory is applied in this study with various boundary conditions. The results obtained in this paper are presented and compared with other results in the references to verify the correctness in implementing the formula and writing the Matlab code. Last but not least, this article can help researchers to have an overview of the free vibration characteristics of the functionally graded porous beams.