Many believe that since the Pekingese is a toy breed that likely spends much of its time indoors, its fur doesn't require much brushing--and that belief is wholly untrue. Pekingese need grooming daily for best results; this frequent care will reduce tangles, matting, and shedding, and simply makes the dog's coat look nicer. If a Pekingese coat does get dirty, try to clean it with a dry shampoo immediately; if dirt/debris are left in the fur, they will become tangled and be impossible to remove without the aid of a professional groomer.
Depending on whether the dog is used in the show ring, many owners opt to give their Pekingese a "puppy cut"--a shorter cut that's generally one length all over--because it's easier to maintain. Regardless of the dog's coat length, daily brushing (along with periodic shampooing) will greatly reduce the need for professional grooming.