A numerical study was conducted for the fully developed laminar flow in rotating curved elliptical pipe.Due to the rotation, the Coriolis force can also contribute to the secondary flow.The interaction of rotation and curvature complicates the flow characteristics.The boundary-fitted coordinate was adopted to study the flow characteristic in the rotating systems.The effects of rotation on the flow transition were studied in detail.The generation and mergence of vortices in rotating curved elliptical pipes were also captured for the first time.The simulation results show that the flow for the case of large aspect ratio of the cross-section is more likely to be unstable than that for smaller one.