A method for detecting touch current leakage of a photovoltaic grid-connected inverter is characterized in that two inverters which are at the same power level share one contact current detecting device; the difference of trigger pulse of the two inverters is equal to half cycle; if the two inverters are the same, the ground parasitic capacitance is completely the same, and thus the AC high-frequency leakage current detected from a common ground wire during the normal work is nearly zero; if the two inverters are not completely the same, the leakage current can be greatly reduced; in case of electric shock under such condition, the proportion of the touch leakage current in the whole leakage current can be greatly increased. Therefore, a small-range current detecting device can be used for detecting the touch leakage current, and as a result, the purpose of accurate measuring can be achieved.