The invention relates to a rubber plug assembly combining device. The rubber plug assembly combining device comprises a first rubber plug assembly provided with a mandrel and a first rubber bowl, a second rubber plug assembly provided with a hollow mandrel and a second rubber bowl, a plug stop assembly fixedly connected with a casing, a first anti-return mechanism and a second anti-return mechanism, wherein the first anti-return mechanism comprises a first anti-return piece arranged on the outer wall of the mandrel and a second anti-return piece which is arranged on the inner wall of the hollow mandrel and used for receiving the first anti-return piece and preventing the first rubber plug assembly from returning; the second anti-return mechanism comprises a third anti-return piece arranged on the outer wall of the hollow mandrel and a fourth anti-return piece which is arranged on the inner wall of the plug stop assembly and used for receiving the third anti-return piece and preventing the second rubber plug assembly from returning. The rubber plug assembly combining device has higher reverse pressure bearing capacity, can avoid return of cement slurry, and a well cementing effect is guaranteed.