The invention provides a pulse signal rail-to-rail peak holding circuit based on high-speed comparator peak searching. The pulse signal rail-to-rail peak holding circuit comprises a high-speed comparator peak searching circuit, a peak reset circuit and a peak holding circuit, which are connected in sequence; the high-speed comparator peak searching circuit is used for detecting a rising edge or afalling edge of an input pulse signal, and outputting a corresponding control signal to the peak holding circuit; the peak holding circuit is used for performing track-to-rail signal tracking or signal peak holding according to the received control signal; and the peak reset circuit is used for outputting a reset signal to reset the peak holding circuit. The pulse signal rail-to-rail peak holdingcircuit provided by the invention adopts a single power supply and achieves input and output rail-to-rail, and the static power consumption is less than 30mW; the peak holding signal has high precision, and the error is less than 1%; the downswing rate of the holding circuit within a peak holding period is low and is less than 1mV/us; and the pulse signal rail-to-rail peak holding circuit has a self-reset function and needs no external reset signal.