To provide a steam trap capable of externally confirming whether foreign matter sticks to an inner surface of a discharge passage and whether a cleaning member is twisted back.

In the steam trap, the float 11 as the valve member leaves from and sits on the valve seat member 9 to open and close the discharge passage 8 and threads the cleaning member 14 to the lid 2 of the valve casing from outside and thereby cleans the foreign matter sticking to the inner surface of the discharge passage 8. The temperature display 31 is attached to the outside surface of the lid 2. The temperature display 31 protrudes from the case 32 when the movable member 39 displaces in the axial center direction of the case 32 by the temperature responding member 40 contracting or expanding by temperature change and the lower temperature display part 41 attached to the one end side of the movable member 39 becomes the predetermined temperature or lower. The distal end of the case 32 from which the lower temperature display part 41 protrudes is twisted back and is positioned to the same protruding position as the distal end of the cleaning member 14 protruding from the lid 2 when the temperature becomes the predetermined temperature or lower.