Abstract: In order to develop the technology of auxiliary power unit for military and civil vehicles, a kind of counter-flow can-type combustor with radial swirler has been properly designed based on turbocharger structure features. Numerical simulation on the 3-D flow in the combustor was performed. The influence of swirler vane angle and structural parameters for air jet orifices on flow field were analyzed. And then, the design of combustor was optimized. The experimental results indicate that the combustion efficient is 0.982, the exit temperature pattern factor is 0.163 and the temperature distribution factor is 0.094. The design of combustor is reasonable, and the combustion properties could satisfy the system requirements.