To provide a draining device which allows efficient washing of a drain pipe by inserting a washing nozzle from the side of a drain port body directly into the drain pipe while maintaining the condition in a cabinet as it is.

The draining device is formed by connecting the drain pipe 20 to a connection port opening into the drain port body 13 via an S-shaped trap 18. The draining device has the two connection ports 14, 15 formed at the drain port body 13, and one of the connection ports 14 is connected to one opening of the S-shaped trap 18 as a draining connection port, while the other connection port 15 is connected to the top of an intermediate bump of the S-shaped trap 18 as a washing nozzle insertion port. Further the washing nozzle insertion port 15 is sealed with a detachable cap 22.