The mechanical smoke exhaust is as acknowledged as an effective smoke control manner by making use of some necessary exhaust facilities, also with more stability than natural exhaust. In this paper, the field model FDS (Fire Dynamic Simulator) with a combination of zone model CFAST (Consolidate Fire and Smoke Transport) were used to simulate the mechanical smoke exhaust in a loop corridor of the fire floor in a high-rise hotel, for the propose of evaluate fire safety of mechanical smoke exhaust. The mainly discussion was about the height of layer interface with the ceiling height changed, also with different smoke exhaust volume. The conclusions were obtained that, when two exhaust vents were set symmetrically in the loop corridor, the volume of smoke exhaust per unit area with 60m3/h according to regulations, always could ensure safety of smoke exhaust. The smoke exhausted worse within the corridor when ceiling height reduced. It was recommended that the ceiling lowest height limit should be provides in correlative regulation.