A similar model experimental platform of flow field in construction period of salt caverns is established based on the similar theory of “selected laws of physics”. The movement rule of flow field in cavity construction period is analyzed by systematic experiments with staining. It finds that the brine migration in reverse circulation of cavity construction can be divided into 6 role zones: buoyant plume zone, convection diffusion zone, buffer diffusion zone, saturated precipitation zone, border dissolution zone and waterfall flow zone. The increase of water injection flow rate accelerates its influence scope and spread speed, but the brine’s movement trend cannot be changed. The change of tube pitch and its spatial location changes the influence scope of water injection flow. Promoting the tube pitch makes the influence scope of fresh water upward, which accelerates the dissolution of upper salt rock. Interlayer changes not only the state of water injection flow, but also the state of boundary mass flow. The more the number of sandwich, the more complex the motion state and the concentration distribution of brine are. With the expansion of the cavity, the relative influence scope of the injection flow and the boundary mass flow become small, and injection water flow’s influence scope gradually goes upward.