A combustor for gas turbine is required to reduce pollutant gas emission. In order to satisfy this requirement, it is needed that combustion process in the combustor is controlled accurately. So, it is important to get an information of interaction between turbulence and combustion. This report deals with aerodynamic phenomena in a swirl type combustor that has two swirlers. Stereoscopic PIV has been used to measure 3-component velocity field of swirling flow without combustion. It was shown that in the swirling flows the interaction of rotational direction is stronger than axial direction. So, two rotating flows are combined and become one rotating flow more quickly. But the distribution of axial direction flow speed is kept to farther downstream as it is.