we arrive in hong kong at 2105hrs on transit to china,is there cheap hotel to sleep for nyt

Do you mean a flight transit or others? If it is a flight transit, you'd better find a hotel not far from the airport. I suggest you take bus S1 from the airport to Tung Chung area. Then find a hotel there to stay overnight. If not, you can take shuttle bus A21 to Tsim Sha Tsui or Hung Hom area. You can find economic hotels there easily.