In the present study, the subcritical flow past a generic side mirror on a base plane is investigated at the Reynolds number of 5.2×105 using delayed detached eddy simulation (DDES) turbulence model. Asides from the capability of capturing main features of the large recirculation vortex in the wake of the side mirror and the front horseshoe vortex, the accuracy of DDES estimation of recirculation length is significantly increased by over 20%, compared to the detached eddy simulation (DES) estimation using the same grid. And DDES prediction of pressure coefficient at the trailing edge of the mirror is in good agreement with the experiments, which is more accurate than both DES and large eddy simulation (LES) results. The results verify the capacity of DDES turbulence model to solve the turbulent flow around the side mirror. This is a key foundation for possible future study of full simulation of external flow field of vehicle.