To provide a clamp of new constitution solving a problem existing in a claw clamp for clamping flange type pipe joints to each other.

The clamp comprises at least one each of a first member 1a arranged at one flange f1, and a second member 1b arranged at the other flange f2. Both members have flange engaging parts 11, 21 and outer edge parts 12, 22 respectively, and the outer edge parts of both members are provided with bolt holes for allowing bolts to pass through in a pipe axis direction from one member to the other member. A plurality of bolt holes are provided in the respective outer edge parts of both members so as to be located in different angle directions viewed from the flange center.