Novel film catalysts of the polystyrene (Ps) and trimethyl phosphate (P) nanoparticles were synthesized on glass substrates by soft chemistry using doctor blade method. Subsequently, the prepared Ps–P film catalysts were characterized by various techniques, including fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), density (d), polarizing microscope (PM), X-ray diffraction (XRD) and thermal analysis. According to the results, the structure and morphology of film catalysts were confirmed by all analyses. The Ps–P films, as heterogeneous solid catalysts, have demonstrated strong activity for Knoevenagel condensation, producing alkenes of high purity. The recovered yields are excellent, up to 96% in solvent-free conditions at room temperature. Further, the film catalysts have showed high stability, good reusability (up to five times) while maintaining their efficiency and productivity