The invention provides a photovoltaic power station electric energy quality optimization method based on active control. The method comprises steps that, step 1, whether an electrical network dispatching command is issued by an electrical network dispatching mechanism to a photovoltaic power station is determined, if yes, a step 2 is performed, otherwise a step 3 is performed; step 2, an active power instruction value of a photovoltaic inverter is calculated, and a step 4 is performed; step 3, largest power point tracking control on the photovoltaic inverter is carried out, and the step 4 is performed; step 4, the active power instruction value of the photovoltaic inverter is issued to the photovoltaic inverter. Through the method, specific subharmonic waves, a harmonic wave distortion rate and flickering in an operation process of the photovoltaic power station are reduced, a resonance problem and a secondary synchronization concussion problem caused by the specific subharmonic waves in the operation process of the photovoltaic power station can be avoided, an electric energy quality standard exceeding problem of an inverter in a low power output state during a limit power operation process of the photovoltaic power station can be effectively solved, and electric energy quality of the photovoltaic power station the operation process can be improved.