The invention provides a photovoltaic power generation maximum power tracing performance index prediction method. Through the building of a time sequence of a photovoltaic power generation maximum power tracing performance index evolution system, the method carries out the non-linear simplex method processing of time sequence measurement data, carries out the reflection calculation of a peak target function, carries out the prediction of a photovoltaic power generation maximum power tracing performance index, and obtains a prediction value of the photovoltaic power generation maximum power tracing performance index. The method can carry out the prediction of the photovoltaic power generation maximum power tracing performance index according to monitoring parameters, carries out the correction control of the maximum power tracing in real time according to calculation results, can effectively avoid power unbalance of all photovoltaic cells, and remarkably improves the reliability and economic performances of a photovoltaic system.