Large eddy simulation (LES) is conducted to investigate coflow jet (CFJ) airfoil flows at high angle of attack (AOA). The Smagorinsky model with Van Driest damping is employed to resolve the subgrid-scale stress. The fifth-order weighted essentially non-oscillatory (WENO) scheme is used for reconstruction of the inviscid flux and the fourth-order central differencing for the viscous flux. The LES results at an AOA of , , , and with momentum coefficients of = 0.15 and 0.08 are compared with the experiment to understand the flow structure of the jet mixing and flow separation. The quantitative prediction of lift and drag and qualitative prediction of vortex structures are in good agreement with experiment.