A diamond type cam for rock climbing, comprising: a body having an operating member provided thereon; a slide member slidably coupled to the body; a plurality of extension cams each of which has one end that is rotatably coupled to the body and the slide member and an extended end portion that is rotatably hinge-coupled, characterized in that the slide member comprises: a first slide piece slidably coupled to the body; and a second slide piece slidably coupled to the body to be spaced apart from the first slide piece for a predetermined distance, wherein the plurality of extension cams comprises: a plurality of first link bars each of which has one end that is coupled to a predetermined position of a circumference of an upper portion of the body at a predetermined interval; and a plurality of second link bars each of which has one end that is rotatably coupled to each of the plurality of first link bars and the other end that is rotatably coupled to a predetermined position of a circumference of the first slide piece at a predetermined interval; and a plurality of wires each of which has one end that is coupled to a predetermined position of a corresponding second link bar and the other end that is rotatably coupled to a predetermined position of the second slide piece. a body having an operating member provided thereon; a slide member slidably coupled to the body; a plurality of extension cams each of which has one end that is rotatably coupled to the body and the slide member and an extended end portion that is rotatably hinge-coupled, characterized in that the slide member comprises: a first slide piece slidably coupled to the body; and a second slide piece slidably coupled to the body to be spaced apart from the first slide piece for a predetermined distance, wherein the plurality of extension cams comprises: a plurality of first link bars each of which has one end that is coupled to a predetermined position of a circumference of an upper portion of the body at a predetermined interval; and a plurality of second link bars each of which has one end that is rotatably coupled to each of the plurality of first link bars and the other end that is rotatably coupled to a predetermined position of a circumference of the first slide piece at a predetermined interval; and the slide member comprises: a first slide piece slidably coupled to the body; and a second slide piece slidably coupled to the body to be spaced apart from the first slide piece for a predetermined distance, a first slide piece slidably coupled to the body; and a second slide piece slidably coupled to the body to be spaced apart from the first slide piece for a predetermined distance, wherein the plurality of extension cams comprises: a plurality of first link bars each of which has one end that is coupled to a predetermined position of a circumference of an upper portion of the body at a predetermined interval; and a plurality of second link bars each of which has one end that is rotatably coupled to each of the plurality of first link bars and the other end that is rotatably coupled to a predetermined position of a circumference of the first slide piece at a predetermined interval; and a plurality of first link bars each of which has one end that is coupled to a predetermined position of a circumference of an upper portion of the body at a predetermined interval; and a plurality of second link bars each of which has one end that is rotatably coupled to each of the plurality of first link bars and the other end that is rotatably coupled to a predetermined position of a circumference of the first slide piece at a predetermined interval; and a plurality of wires each of which has one end that is coupled to a predetermined position of a corresponding second link bar and the other end that is rotatably coupled to a predetermined position of the second slide piece.