The porosity distribution, which varies through-thickness direction, plays a vital role in affecting the microstructure and mechanical properties of the final product. This study develops numerical and experimental techniques for the analysis of functionally graded nanobeams with porosity (PFGM). Taking a porous polymeric functionally graded structure as an example, a novel beam can be applied to a broad variety of engineering and biomaterial applications. Tensile specimens were prepared using 3D printing, while flexural bending specimens reinforced with 5% (Al/Al2O3) nanomaterial were made using a special system. To study the performance of functionally graded beams with various porosity distributions, numerical solutions were obtained using finite element methods (FEM) and simulations were conducted in ANSYS software. By comparing the obtained results with those obtained from numerical calculations, the experimental solution, including the bending load and midspan deflection, was validated. Additionally, several parameters, such as the porosity parameter, polymer type, and geometrical characteristics, have been studied for their effect on the flexural strength of functionally graded beams. According to the results, it is found that there is a significant effect of the porous parameter and gradient index on the static behavior of functionally graded beams, and nanoparticles enhance bending resistance.