In modern years, solar energy has developed as the leading Renewable Energy Source (RES) and is widely utilized across various applications. Photovoltaic (PV) system built rapidly when compared with other conventional electrical plants because of its cost saving, less maintenance, ease of installation and long-term investment. Therefore, this research focuses on a PV system powered by Single Ended Primary Inductor Converter (SEPIC) regulated using Proportional Integral (PI) controller optimized through metaheuristic-algorithm. The proposed SEPIC converter step-up and step down the input voltage with same polarity to produce a stable output with higher efficiency and better performance. In order to normalize the output voltage from the converter, PI controller is applied by eliminating steady state error. The error signal fed to Pulse Width Modulation Generator (PWM) which generates pulses to attain high efficiency. The performance of PI is enhanced using a Grey Wolf Optimized (GWO)-based method, where the metaheuristic algorithm by tuning the PI parameters to solve optimization challenges in the system, resulting in superior performance effortlessly compared to the conventional PI controller. Simulation results obtained through MATLAB demonstrates superior performance in maintaining stable outputs of the system. The proposed converter achieved higher efficiency of 94% compared to other DC-DC converters. The proposed GWO achieves less rising and settling time as 0.04s and 0.1s compared to PI.