Polyarylene ether nitrile (PEN), a kind of high-performance polymer, has attracted considerable attention from the polymeric research community owing to its extraordinary properties, including radiation resistance, high thermal stability, high dielectric properties, and good mechanical properties. In our study, due to the good interaction between carbon dioxide (CO2) and C-F, we synthesis a new kind of FPEN with CF3 group. After that, novel structure of lightweight high-performance FPEN foam was prepared, through the introduction of supercritical carbon dioxide by batch foaming method. In this study, we prepared the different FPEN foams structure and investigated the different foam condition effect on the FPEN foams. Moreover, we can change the foaming time, absorption pressure, and foaming temperature to prepare different structure of FPEN foams. The mechanical measurement results show that the different structure of FPEN foams exhibited different tensile strength, elongation of break and impact strength. Meanwhile, this technology to prepare different structure foams not only decreases the weight of the samples but also improve the specific tensile and impact strength. Moreover, the appearance of sample prepared by this method is also can be controlled and looks very smooth. The remarkable mechanical properties with good surface appearance show a promising usage in offering lightweight in many advanced applications like the automobile structural components.