A trapless water flush toilet bowl fixture is disclosed. This fixture has: a water closet cesspool sealing member pivotally supported to shut off a waster water discharge port by impinging from underside upon this port; a sinker imparting a sufficient impingement force applied on a lower surface of the discharge port to the water closet cesspool sealing member to maintain a sealing state while resisting a load created when utilizing the same fixture; and a separating force imparting member manipulated by a manpower which member is capable of separating the sealing member from the discharge port by overcoming the impingement force. Furthermore, the trapless water flush toilet bowl fixture subsumes: a bowl having the waste water discharge port formed downwards in the bottom; a cylindrical member arranged to be nearly concentric with respect to the discharge port so that waste materials in the bowl pass therethrough and drop down, the cylindrical member having its diameter that is substantially the same as an aperture of the discharge port; and a ring-shaped seal-packing attachable to and detachable from an inner surface of the lower end of the cylindrical member; and a closing member provided at the lower end of the cylindrical member and making a seesaw motion round a fulcrum, this closing member subsuming a dish-like member which impinges from underside upon the seal-packing and a sinker installed on the opposite side to the dish-like member while interposing the fulcrum therebetween. In this constitution, the seal-packing is attachable to and detachable from the inside of the cylindrical member.