A pulsed ion multifunctional detector used for both high performance liquid chromatograph and ion chromatograph, and experiment chromatograms attached also show that the detector has excellent multipurpose function in liquid chromatograph. The casing of the instrument is provided with a sample solution inlet, a sample solution outlet, a power supply socket, a liquid crystal display, an operation keyboard and a detection signal output interface. In the casing is provided a detection electromechanical member, which includes a central controller, a detection cell, a preposed subtracting module, a polarity transformation module, a noise processing module and an output amplifier module. The pulsed ion multifunctional detector can sensitively and accurately measure ion current of sample ionized directly in the detection cell, and subtract baseline background generated by various mobile phases and automatically eliminate dynamic noise and drift of the instrument.