Three-dimensional viscous flowfields in two different types of cascades, such as a turbine nozzle and fan blade, were numerically simulated by solving the Navier-Stokes Equations. For turbine nozzle flows, computed flow patterns on a vane in stationary and rotating frames were compared with those on a differently stacked vane. In a fundamental case, the computed results showed good agreement with experimental data. Three-dimensional flow separations as well as secondary flows caused by passage vortices could be predicted and effectively visualized using surface oil flow and streakline techniques, which were useful methods of three-dimensional flow representation.