Abstract: The turbine of heavy duty gas turbine was studied by one-dimensional and quasi three-dimensional method,including mode design and optimization.The quasi three-dimensional calculation was based on the result of the one-dimensional optimization,and the quasi three-dimensional result was optimized.The result shows that the efficiency increases 0.8% by the one-dimensional optimization,and the outlet flow angle is close to 90 degree.There is transonic flow in the flow path of the second and third stator.In the quasi three-dimensional calculation,the cool air mix loss takes an important part in the total loss,due to the large quantity of cool air in the first stage.The secondary loss is a great factor to impact the loss distribution along blade height.The loss is decreased by the quasi three-dimensional optimization,especially in the third stator.The purpose of this study,refer to the general F-class turbine aerodynamic design experience,to discuss gas turbine design on how to choose one dimensional,quasi three-dimensional parameters,so as to provide cascade reference to the engineering design.