To provide a washing brush for a water drain basket for receiving garbage in a sink being sanitary and capable of scrubbing and washing an inner face of the water drain basket by easy operation without making a user have uncomfortable feeling and scratching the user and providing ease of use.

This washing brush is stored in the water drain basket 4 for receiving garbage in the sink 2 and is rotated and operated to scrub and wash the inner faces A, B of the water drain basket 4 in order to remove soil and slime of the water drain basket 4.