In this study, the virtual flow of fluid in the Riemann surface is simulated by taking advantage of the numerical simulation that can create any situation. Specifically, it is assumed that one elliptical column is placed in two Riemann surfaces and three Riemann surfaces, and a uniform flow is applied to them. The incompressible Navier-Stokes equation is used as the basic equation, and the equation is solved numerically using the standard MAC method. The Reynolds number is set to 200, where Karman vortices are generated and the result is compared with the actual flow. When there are two Riemann surfaces, when the flow of uniform flow is slightly changed on the two surfaces, the phase of the Karman vortex is slightly shifted accordingly. In the case of three Riemann surfaces, the twin vortex flow and two kind of Karman vortex flow that is approximately 180 ° out of phase appeared on each surface.