This paper explores the augmentation of thermal conductivity in paraffin wax through the incorporation of aluminum oxide (Al2O3) and copper oxide (CuO) nanoparticles, leading to the development of composite phase change materials (PCMs). The objective is to enhance heat transfer rates, crucial for various energy storage applications including industrial waste heat recovery and solar thermal energy storage. Differential Scanning Calorimetry (DSC) testing was employed to experimentally investigate the thermal properties of the resulting nanocomposite PCM.The experimental results reveal that the nanocomposite PCM, composed of 96.14% paraffin wax, 2% aluminum oxide, and 1.6% copper oxide, exhibits 1.35 times increase in heat transfer rate compared to conventional paraffin wax. The integration of nanoparticles into the PCM matrix, facilitated by a magnetic stirrer at 50°C for 4 hours, results in uniform distribution and improved grain morphology, as evidenced by SEM images. Moreover, the composite PCM demonstrates superior performance, surpassing paraffin wax by 1.35 times during heating and 1.5 times during cooling, while maintaining similar peak temperatures. The normalized enthalpy of the composite PCM exceeds that of paraffin wax by 1.25 times, highlighting enhanced energy storage capacity. The significant enhancements in thermal conductivity and phase change behavior are attributed to the presence of aluminum oxide and copper oxide nanoparticles. Notably, an optimized composition comprising 96.15% paraffin wax, 2.15% aluminum oxide, and 1.7% copper oxide Considered by mass demonstrates a delicate balance between improved thermal properties and material stability. This study underscores the immense promise of nanoparticle - enhanced composite PCMs as a transformative solution for enhancing thermal energy storage efficiency, with implications for sustainable energy technologies. Future research should focus on further refining composite PCM formulations, assessing long-term stability, and exploring practical applications, particularly in solar thermal energy storage systems.