With the development at infrared guidance weapon, the survival of the ship, especially in high risk areas, is facing serious challenges. In order to improve its survival ability, infrared suppression system emerges. Marine gas turbine exhaust ejector system is its core component, which is responsible for reducing or even eliminating the infrared radiation signal of marine gas turbine exhaust system. Based on collecting data on many sorts of ejectors, we sort out literature related to gas turbine exhaust ejector. From the view of ejector structure, the paper briefly describes the development of gas turbine exhaust ejector used on ships in domestic and foreign. Put forward two major structural innovations: the structure of nozzle changes from circular to rectangular and diffuser adopts multilevel structure. A new type of marine gas turbine exhaust ejector was designed. Ejector model is simplified. Use numerical simulation method to predict the single-stage ejector and multistage ejectors. Further structural optimization plan and design can be made based on this essay.