Research conclusions: From the study on the development and design of reserved top—head platform of Shenzhen Qianhai Subway Car Depot，it is concluded(1)The design of reserved top—head platform of Car depot for fire protection should be made in accordance with the real condition of each building and the suitable measures should be taken to meet the requirements of fire protection．(2)The problems in the fire protection of Car depot should be overcome by adopting the current technologies for fire protection with the Security Code and Standard．(3)The heat insulation measure with fire—proof coating should be taken or the protective layer for the members of the beam and plate should be thickened to meet the requirement of 4—hour fire resistance and the construction demands．