The superalloy and protective coating is a major trend of material used in spacecraft engine. With the rapid development of space exploration technologies, it is very important to design a new type of Nb-W alloy and its coating used in the field of spacecraft engine for the upgrading weight ratio and operating temperature. This study controls the ratio of Nb, W, Zr and other elements to sintering and gets a new type of Nb-W alloy Nb521-1 with excellent mechanical properties at high temperature by electron beam furnace smelting. Using slurry firing, the silicide complex coating was prepared on the surface of Nb521-1 alloy. The morphology of the composite coating was investigated by SEM. The life of high temperature oxidation resistance is at least 50 hours at 1700℃ and 9 hours at 1800℃. The limit time of shock-testing from room temperature to 1600℃ is more than 2500 times. Complex coating achieves the goal of high temperature oxidation resistance protection. Products have been successfully applied in aerospace materials.