The underwater glider,a new kind of underwater vehicle,has the advantages of low-noise,long range,long duration and cost-efficiency.This paper analyzes the driving mechanism and motion realization of underwater gliders,presents the simulation result of its typical motion modes,then describes the overall arrangement of an underwater glider test model being designed,and finally discusses the design and selection of the glider's buoyancy adjusting mechanism,pitch adjusting mechanism and roll adjusting mechanism in detail.