Power quality is the main concern in power distribution systems. Poor power quality could cause disturbance and financial losses to consumers. It may also cause electrical appliances to overheat, damage and operate in undesired regions. Other than that, power distribution components such as transformers could also experience core saturation and overheating to the winding. This paper investigates potential power quality issues in a photovoltaic-grid connected power system. A real-life power distribution system is first modelled in PSCAD and it is then integrated with a photovoltaic system to form a micro-grid power system. Several case studies are conducted to identify any potential power quality issues with the micro-grid power system. The simulation results shows that the micro-grid power system experiences various power quality issues, such as inrush current, power fluctuation, frequency fluctuation, harmonic distortion and low power factor.