The invention belongs to the technical field of finding of power distribution line grounding fault points and particularly relates to a signal transmitter for finding power distribution line grounding fault points. The signal transmitter for finding power distribution line grounding fault points comprises a signal transmitter body, wherein the signal transmitter body comprises a shell; a high-voltage output terminal, a main grounding terminal and a power input port are arranged on the shell; a high voltage generation circuit is arranged inside the shell and comprises a transformer T1, a high-voltage rectifying circuit ZL, a capacitor C1, a resistor R1 and a signal transmitting switch SW1; the input end of the transformer T1 is electrically connected with the power input port; the output end of the transformer T1 is electrically connected with the input end of the high-voltage rectifying circuit ZL; the capacitor C1 is in parallel connection with the output end of the high-voltage rectifying circuit ZL; a positive output end of the high-voltage rectifying circuit ZL is successively connected in series with the resistor R1 and the signal transmitting switch SW1 and is subsequently electrically connected with the high-voltage output terminal; a negative output end of the high-voltage rectifying circuit ZL and a grounding end of the signal transmitting switch SW1 are both electrically connected with the main grounding terminal.