A pipe coupler is provided to manufacture integrally a connection pipe and a joint pipe, so that a pipe connection work is simply performed. A pipe coupler includes a connection pipe(300) and a joint pipe(100) so that the connection pipe is coupled to the joint pipe by using a clamp(200). The joint pipe includes a pipe part(120) connected to a pipe and a flange part(110) expanding at one end of the pipe part. The connection pipe includes a pipe part(310) connected to the pipe and a flange part(320) expanding at one end of the pipe part. The flange part of the connection pipe is inserted into the flange part of the joint pipe. The clamp includes a pipe part(210) pressing the flange part of the connection pipe and a flange part(220) fixed to the flange part of the joint pipe.
