A tissue ligating device comprises a first fixation part to which a base end part of a suture thread is fixed and a second fixation part configured to allow insertion of the suture thread therethrough and allow to be crimped so as to newly fix a part of the suture thread, and thereby to define a loop starting from the base end part, in a state after ligation of tissue is performed. The second fixation part includes a back side wall part, a front side wall part, and a curved wall part turning back from the back side wall part to the front side wall part. An end part of the front side wall part far from the curved wall part is inclined or curved towards a front side.
