Abstract: This paper reviews the composition and the design of the mockups for weightless underwater training in different periods. It is shown that the accurate simulation of the human-machine interface is an important point for the construction of the underwater mockups. In order to simplify the construction process, the mockup fidelity can be graded according to the experimental requirements. The adaptability to the underwater environment should also be considered in the design, including the reasonable selection of the materials and the design of the neutral buoyancy equipment. This review provides some guidance for the underwater mockup design in China.