The invention relates to an experiment method for simultaneously monitoring the movement state of high-concentration particles and a liquid flow field in cracks. The method includes the following steps that tracing particles and first spherical particles are placed in a particle tank; the tracing particles, the first spherical particles, a fluorescent tracer agent and liquid are prepared into a mixed solution; the mixed solution enters a shaft through a screw pump and enters the cracks through a shot hole in the shaft; a particle image speed measuring system is used for photographing the mixed solution in the cracks, and the shot images are subjected to data processing; the mixed solution flows out from outlets of the cracks and enters a filtering tank through a pipeline; the mixed solution filtered by the filtering tank flows into a liquid tank again through a centrifugal pump. In a high-concentration particle group composed of the tracing particles and the first spherical particles, the tracing particles are tracked through the particle image speed measuring system, and movement characteristics of the single particle are obtained; meanwhile, the liquid flow field is analyzed out by the particle image speed measuring system according to the images of the fluorescent tracer agent in the collected liquid.