a power plug having leakage current protection function is disclosed . the power plug includes a changeover mechanism for making and breaking electrical connection between the input and output side of the plug , and a control circuit for detecting a leakage current and a short circuit . a reset button and a test button are provided . when the reset button is pressed , a reset shaft operates the changeover mechanism to achieve electrical connection between the input and output sides . when there is a current leakage , a short circuit or other abnormal conditions at the output side of the plug , the control circuit generates a signal to operate the changeover mechanism to electrically disconnect the input and output sides . the test button can simulate a short circuit to electrically disconnect the input and output sides .