<p>This article presented a comprehensive and accurate nonlinear mathematical model to analyze the mechanical response of multi-directional functionally graded material porous (MDFGMP) plates, for the first time. The model includes a differential quadrature method (DQM) with a quasi-3D theory to investigate bending and vibration responses MDFGMP plates. A nonlinear quasi-3D plate theory is exploited to present the kinematic fields including the effect of normal strain, thickness stretching, and satisfy the zero-shear strain/stress at the top and bottom surfaces without shear correction factor. The power 3D function distribution is used to portray gradation of material constituents through thickness and in-plane directions. Two types of porosity are selected to describe the distribution of voids and cavities through the thickness of the plate. Hamilton’s principle is employed to derive the nonlinear governing differential equations of motions in terms of stress resultants. The differential integral quadrature method (DIQM) is manipulated to discretize the structure spatial domains. The accuracy and reliability of the proposed method have been validated by comparing its numerical results to those of available works. Parametric studies are provided to exhibit the significant impacts of kinematic normal and shear relations, gradation indices, porosity type, and boundary conditions on MDFGMP plates. It is found that frequency mode shapes are symmetric for homogeneous plates but exhibit non-symmetric profiles if the material properties change in the in-plane directions. In contrast, changing material properties in the thick direction, although changing the frequencies, it preserves symmetric mode shape patterns. The present model and results can be implemented as benchmarks for future nonlinear mechanical response of MFGMP plates structures. The proposed model can be implemented in selection and design of the nuclear reactors, marine and aerospace structures manufacture from MDFGMP plates.</p>