The invention discloses a middle draining device for desalted water. The middle draining device comprises a main pipe (1) of the middle draining device and even number of branch pipes (4) of the middle draining device, wherein the branch pipes are fixed at two sides of the main pipe (1) of the middle draining device, the branch pipes (4) of the middle draining device are symmetrical relative to the main pipe (1) of the middle draining device, one stripe-shaped reinforcing rib (3) is fixedly connected at the bottom of each branch pipes (4) of the middle draining device, and a hoop body (5) is also arranged at the blind end of the main pipe (1) of the middle draining device. The middle draining device has simple structure, is easy to manufacture and has long service life.