Abstract: At present,advanced aircraft turbines make a feature of low aspect ratio,transonic flow in cascade passage,high aerodynamic load and intensive cooling.In order to predict their characteristics the AMDC formula for cascade loss is corrected on the basis of the so-called KQ system（3）as formula（3）.In accordance with the experimental results of transonic cascades obtained in our country,the AMDC formula for supercritical wave drag is then modified into formulas（4）and（5）for transonic and high subsonic turbines respectively. For the sake of eliminating the cascade choke conditions which do not exist in fact but often occur in calculation,a suitable relation for the flow angle at cascade exit is proposed.The prediction method takes into account the various operating conditions,including subcritical,critical and supercritical expansions,limit supercritical expansion and limit loading,and a computer program has been written.The characteristics of a transonic and a high subsonic turbine models and the design performances of a cooled turbine with low aspect ratio have been predicted with this method,and compared with test results in good agreement.It is shown that the accuracy is about 99 percent.