In recent years, the increasing use of renewable energy sources has led to the deployment of photovoltaic (PV) systems in the power grid. However, the intermittent nature of solar power poses challenges in maintaining power quality and stability. In this study, we propose the optimization of on-grid systems with PV-STATCOM for efficient reactive power compensation. The PV-STATCOM system integrates a photovoltaic array with a static synchronous compensator (STATCOM) to achieve optimal voltage regulation and power quality control. The proposed system is modelled and simulated using MATLAB/Simulink software. Results show that the optimized PV-STATCOM system effectively compensates for reactive power, reducing system losses, and improving voltage regulation, leading to improved power quality.