The present invention discloses a pin plate oil clearance partial discharge modeling and analysis method under a compound voltage. The method comprises the steps of: constructing a model of transformer oil insulation partial discharge pin plate electrodes under the compound voltage, adding influences effects of electrons, positive ions and negative ions on propagation and development of a streamerto the model to describe head conduction of temperature change in the transformer oil to obtain a final simulation model; classifying the types of partial discharge between the oil clearance pin plate electrodes to determine the type of leading partial discharge when the compound voltage containing alternating current components is applied to the simulation model of the pin plate electrodes; andchanging the voltage applied on the pin plate clearance of the simulation model or the width of the pin plate clearance to obtain the rule of change of each partial discharge type with time.