A tube assembly for delivering a substance is provided. The tube assembly includes a tube body, a sleeve body, a joint member, a handle member and a fixing member. The tube body has a tube end portion. The sleeve body is fitted around the tube body and has a sleeve end portion corresponding to the tube end portion. The tube end portion is fitted around one end of the joint member. The handle member is fitted around the sleeve body. The fixing member is fitted around the sleeve end portion, the handle member and the joint member at the same time so that the fixing member presses a part of the handle member, a part of the sleeve end portion and a part of the joint member inwards in a manner such that the tube body, the sleeve body and the handle member are fixed relative to the joint member.