The numerical simulation method was used to carry out a systematic study on the roll control of the flying wing using the trailing-edge CC(circulation control) jet at a wide speed range (Ma为0.145～0.7), and was compared with the configuration controlled by classical control surfaces. Research focuses the electromagnetic stealth characteristics, the roll control characteristics and their flow physics, and the impacts of the bleed air. Results show that as the Mach number increases, the roll control capability of the CC jet decreases due to the weakening of entrainment and blocking effects. However, the CC jet enhances the stealth performance at specific azimuth ranges remarkably. Moreover, it requires less bleed air, induces less thrust loss, and has a high control efficiency factor (aerodynamic moment coefficient produced per unit of additional drag coefficient). In conclusion,the trailing-edge CC jet is a highly promising roll control device for a flying wing.