The invention provides a zero voltage PFC (Power Factor Correction) convertor, which comprises a main power unit 101, an output voltage detection unit 102, an error amplification unit 103, a logic control unit 104, a driving unit 105 and a negative current detection unit 16, wherein the first output end SW1 of the driving unit 105 is connected with the grid electrode of a main switching tube in the main power unit to control the main switching tube to be on and off; the second output end SW2 of the driving unit 105 is connected with the grid electrode of a synchronous rectification pipe in themain power unit to control the synchronous rectification pipe to be on and off; and when the negative current detection unit 16 detects that inductance negative current achieves a set current threshold value, cutting off the synchronous rectification pipe. Under a condition of different instantaneous input voltages subjected to alternating current input, the conduction of the main switching tubeis fixed time, and a PFC function is realized. By use of the convertor, under a high-voltage input condition, zero voltage conduction and the PFC function still can be realized so as to be favorable for improving efficiency during the high-voltage input of a product and be more favorable for realizing product high frequency and miniaturization.