This study investigates the performance and highlights the mechanical, thermal, and vibrational characteristics of hybrid fibre composite plate composed of Kenaf Fibre (KF), Ridge Gourd Fibre (RGF), Waste Plastic Materials (WPM), and matrix materials. The raw materials undergo an alkaline treatment involving 2 hours of agitation with 5% NaOH. Following treatment, KF, RGF, and WPM are combined with epoxy resin using compression moulding to form four different hybrid composite plates in the %wt of 10:20:5, 20:10:5, 10:10:5, and 20:20:5. Various tests are conducted to evaluate their properties, including the Tensile Test, Shear Test, and Flexural Test, adhering to ASTM standards D638, D7078, and D790, respectively. The results indicate that 20:20:5 plate showed higher tensile strength (21.70 MPa), flexural strength (77.23 MPa), and shear strength (18.13 MPa. Subsequently, Thermo gravimetric Analysis (TGA) was conducted on the 20:20:5 composite plate due to its superior mechanical properties than other propositional plates and achieved peak temperature at 432.53OC. finally, all four hybrids composite plates were underwent vibration tests using impact hammer method experimentally, where the fundamental frequencies, damping ratio, and amplitude have better consistency on 20:20:5 plate compared to other combinational plates as well existing available literatures. So, the 20:20:5 proportional composite plate has significant applications in the manufacturing aircraft, automotive, thermal energy devices and construction industries respectively.