Abstract: A reading desk for use in a sitting or lying position includes a downwardly open box-shaped housing secured to the ceiling of a building, a take-up roll mounted within the housing, a rotation assembly mounted at one side of the take-up roll to rotate the take-up roll in the forward or reverse direction, a pair of belts, each of which has one end connected to the take-up roll to be wound on or unwound from the take-up roll and the other end extending downward from the housing, and a book holder having an upper portion connected to the other ends of the pair of belts and adapted to ascend or descend by the operation of the rotation assembly to be inserted into the housing or exposed to the outside.