The invention discloses a road lamp monitoring method for fault positioning based on electric leakage detection. The method comprises the following steps: setting an electric leakage danger level and an electric leakage voltage threshold value in a road lamp circuit; detecting electric leakage current in a null line circuit and a live line circuit of the road lamp circuit; detecting electric leakage voltage between a ground wire of the road lamp circuit and a lamp pole; when a monitoring system detects that the electric leakage current is zero and the electric leakage voltage is not zero, determining that electric leakage occurs at a cable between lamp poles in the road lamp circuit, and calculating to obtain the electric leakage position; when the monitoring system detects that the electric leakage current is not zero and the electric leakage voltage is not zero, judging the electric leakage danger level in the road lamp circuit according to the electric leakage voltage, displaying the electric leakage danger level, and turning off a road lamp when the electric leakage voltage is equal to or greater than the electric leakage voltage threshold value. The road lamp monitoring method can judge the electric leakage danger level and obtain the accurate position subjected to electric leakage.