A condensate trap apparatus comprising: an inlet , through which condensate is introduced; a storage space , in which the condensate introduced from the inlet is stored; a discharge part including an outlet configured to discharge the stored condensate from the storage space ; and a buoyant body including a closed part formed to be convex toward a vertically lower side such that the buoyant body is seated on the discharge part to close the outlet , and a columnar support part extending vertically upwards from the closed part , characterized in that the discharge part further includes: an annular discharge packing surrounding the outlet , extending from an edge of the outlet to be inclined toward a radial outside of the outlet and a vertically upper side such that an outer surface of the buoyant body contacts the discharge packing when the buoyant body is seated on the discharge part to close the outlet , wherein the discharge packing has a dual structure including: an annular first contact part disposed on an outermost side with respect to a radial direction of the outlet and contacting the closed part ; and an annular second contact part located to be spaced apart from the first contact part inwards, and contacting the closed part . an inlet , through which condensate is introduced; a storage space , in which the condensate introduced from the inlet is stored; a discharge part including an outlet configured to discharge the stored condensate from the storage space ; and a buoyant body including a closed part formed to be convex toward a vertically lower side such that the buoyant body is seated on the discharge part to close the outlet , and a columnar support part extending vertically upwards from the closed part , characterized in that the discharge part further includes: an annular discharge packing surrounding the outlet , extending from an edge of the outlet to be inclined toward a radial outside of the outlet and a vertically upper side such that an outer surface of the buoyant body contacts the discharge packing when the buoyant body is seated on the discharge part to close the outlet , wherein the discharge packing has a dual structure including: an annular first contact part disposed on an outermost side with respect to a radial direction of the outlet and contacting the closed part ; and an annular second contact part located to be spaced apart from the first contact part inwards, and contacting the closed part . an annular discharge packing surrounding the outlet , extending from an edge of the outlet to be inclined toward a radial outside of the outlet and a vertically upper side such that an outer surface of the buoyant body contacts the discharge packing when the buoyant body is seated on the discharge part to close the outlet , wherein the discharge packing has a dual structure including: an annular first contact part disposed on an outermost side with respect to a radial direction of the outlet and contacting the closed part ; and an annular second contact part located to be spaced apart from the first contact part inwards, and contacting the closed part . an annular first contact part disposed on an outermost side with respect to a radial direction of the outlet and contacting the closed part ; and an annular second contact part located to be spaced apart from the first contact part inwards, and contacting the closed part . <EOS>