Abstract: In order to gain higher specific impulse, the rocket turbines for the closed cycle are reaction turbines with a lower reaction in the rotating vanes. This rocket reaction turbine is characterized by lowest pressure ratio,highest load and low aspect ratio. Under the design conditions of large medium flow deflective angle in the turbine cascade, low aspect ratio and large relative rotor tip clearance, the positive attack angle design along the height of the vanes,varying load and varying loss design along the height of the vanes are adopted in order to minimize the secondary loss,the tip clearance loss and gain the high efficiency for the rocket reaction turbine.