Abstract: The experimental results of a certain compressor stator tandem cascade (abbreviated as C-cascade) which profile is approximate to C-4, and a double circular are tandem cascade at high subsonic speed are presented in this paper. These two types of cascade were tested in a cascade wind tunnel at free stream Mach number Ma1 =0.55 to 0.75 and incidence angles I =-5 to +7.5. The experimental results are illustrated as plots of the variations of air-turning angle △β, static pressure rise coefficient cp and total pressure loss coefficient w against incidence angle I. The optimum values obtained for both tandem cascades are as follows (for Maj 0.7):C-cascade 0° 57.7°0.106 0.31double circular 0° 54° 0.136 0.35