Abstract: Up to date, simulation of subsonic flows over the high lift device is still a challenge, especially for the cases with higher angles of attack. In order to evaluate the ability of HyperFLOW, an in-house CFD software for subsonic turbulence flow over complex geometries based on structured and unstructured grids, the NASA high lift trap wing model is selected and investigated. Two cases discussed in the NASA high-lift workshop are considered on three types of grids, i.e. two unstructured or mixed grids, and one multi-block structured grid. The simulations on coarse, medium and fine grids for each type are carried out to access the performance of grid convergence. The numerical results are analyzed using Richardson extrapolation method, and compared with the experimental data and the results by other famous CFD codes in the world. The comparison demonstrates that HyperFLOW has a good property of grid convergence on different grids. As the statistical conclusions of the NASA high-lift workshop, the numerical results are acceptable within the linear part of the aerodynamic forces in the regime of lower and medium angles of attack. However, it is still a challenge for the prediction of the cases in higher angles of attack, especially for the cases near stall.