Vehicle auxiliary braking system is very significant to the brake safety. The eddy current retarder (ECR) has a good braking performance, but the braking torque would fade under high speed domain. In the contrary, the regenerative brake (RGB) could provide a satisfied braking performance in high speed domain. However, the braking torque in low speed domain is insufficient. This paper proposed a novel concept of the integrated energy-recuperation retarder (IEER), which would take advantage of the merits of both the ECR and the RGB to have a steady braking performance in all-speed domain.The IEER integrates the structures of rotary eddy current retarder (RECR) and the RGB, both of which share a stator. Braking torque of the IEER produced by stator core and armature-windings can stack together, and therefore the IEER can provide greater braking torque than the RECR. Besides, the IEER can recover electric energy from armature-windings. The IEER can weaken the recession of braking torque effectively, and possess a high electric energy-recovery power in theory.This paper aims at the matching of the braking torque and the electric energy-recovery power. Firstly, the braking torque’s mathematic models of the IEER and the RECR are derivate respectively, and the electric energy-recovery power’s mathematic models of the IEER and the RGB are also established respectively. Then, the simulation tests based on MATLAB/SIMULINK are set up considering the variables of the rotating speed, and the finite element method is applied in Ansoft Maxwell considering the Inhomogeneous magnetic field in the IEER. Finally, braking torque’s property of the IEER and the RECR, and electric energy-recovery power’s property of the IEER and the RGB come out. The simulation results reveal the obviously smaller recession of the braking torque compared with the RECR, while the electric energy-recovery power is nearly identical to the RGB.