Evaluating method of aerodynamic performances of scramjet engines by using multi-probe rakes was proposed. The aerodynamic tests of engines were carried out under Mach 4 flight conditions. Comparison of Pitot pressure distribution and gas sampling by the rakes enable to investigate the mixing rate of fuel gas in the engine. The accuracy of the rake measurement was examined. Using the rakes enables measurement of mass flow within 2% and thrust within 1%. The air capture ratios of various inlets were also independently measured by the rakes and a conventional choked flowmeter. The air capture ratios measured by these two methods agreed within 2%. The advantages of the rakes to the flowmeter were reported. It was found that the rakes enable to measure the air capture ratio more simply than the flowmeter.