Abstract: Four sets of composite air-cooled blades of highly-loaded and high temperature transonic turbine with various schemes of film-cooling holes have been designed and made,and have successfully passed 290 hour test run.Experimental results show that the cooling characteristics of the turbine vanes and blades are superior as their cooling mass flow ratios are 2-8% and 1-6% respectively.The wall temperature of turbine vanes and blades were corrected by measuring the heat losses of the test section.The results are converted to actual engine operation conditions,according to the similarity theory.It is obtained that the cooling effectiveness of the turbine vanes and blades is 335-420K respectively,and the wall temperature distributions are uniform.The effects of the parameters of the air-cooled turbine blades on the cooling effectiveness are also considered systematically,based on a large quantity of data obtained from the experiments of four kinds of composite air-cooled transonic turbine vanes and blades.