A stripper and a stripping process for removing the flue gas carried by regenerated catalyst. A cylindrical stripper mainly comprises a degassing pipe at the longitudinal axis, a horizontal pipe connected with the lower end of the degassing pipe, several sets of inner annular baffles and outer annular baffles arranged in alternative arrangement along the vertical direction. Inner annular baffles are fixed on the degassing pipe, outer annular baffles are fixed on the inner wall of the cylinder. The degassing pipe has holes below each set of the inner annular baffles. The regenerated catalyst enters the stripper from the upper part, comes into a countercurrent and crosscurrent contact with steam from the annular steam conduit, and the stripped regenerated catalyst leaves the stripper from the bottom. The removed flue gas and the excessive steam enter the degassing pipe through the opening part of the degassing pipe under each set of inner annular baffles and leave the stripper from the top under the action of steam or air from the horizontal pipe. Using this stripper can minimize the amount of the flue gas carried by regenerated catalyst.