The invention discloses a synchronous triggering system based on multipath measurement signals. The system comprises an initial signal triggering unit, a test line, at least two measuring instrumentsand at least one oscilloscope. The first measuring instrument is arranged at an initial triggering point of the test line; starting from the initial triggering point, the test line is provided with measuring points in sequence at an interval of not more than 100 m; the initial signal triggering unit sends multiple paths of initial triggering signals from the initial triggering point of the test line to the test line, and the initial triggering signals are input to the oscilloscope after passing through an electro-optical conversion module and an optical-electric conversion module simultaneously; each measuring point of the test line measures an electrical signal through the measuring instrument, and the electrical signal of each measuring point except the initial triggering point is inputto the corresponding oscilloscope; and the oscilloscope is used for receiving initial triggering signal waveform and electric signal waveform of each measuring point, and recording the waveforms.