A coupling device for circular pipes, in which locking rings, inserted into a body to clamp a circular pipe, are arranged in a pair so that the central line of a circular pipe can be aligned when the circular pipe is inserted. Furthermore, the degree to which the body presses the seal packing can be adjusted so that a reliable seal can be maintained and the circular pipe can be securely coupled no matter who uses the coupling device. A coupling device for corrugated and circular pipes is provided for the case where it is more effective to replace one of the circular pipes with a corrugated pipe. The first coupling section and a connecting means, which can engage with a corrugated pipe, are provided opposite the second coupling section, which is coupled with the circular pipe.