The invention provides a fault positioning method based on GPS and current waveform. A multi-power-source power supply system comprises at least two power source ends. The power source ends are connected through a plurality of power distribution terminals; and every two power source ends form the unique channel connection through the power distribution terminals. The method comprises the following steps: carrying out AD sampling on current of each power distribution terminal; and for each distribution network node, carrying out comparison between every two waveforms of sampling currents of the adjacent m power distribution terminals and judging whether two power distribution terminals, whose waveform slope signs are opposite, exist, and if so, judging that the fault point is located between the adjacent m power distribution terminals, wherein the m is not less than 2. Each power distribution terminal is provided with a GPS module, and time synchronization is realized through the GPS module, thereby guaranteeing that the AD sampling current of each power distribution terminal is synchronous.