Research conclusions： Several factors should be taken into account during the design of water supply and drainage system and fire fighting system of railway tunnel crossing a river according to our research and discussion on the design of Shiziyang Tunnel crossing Pearl River on the Guangzhou-Shenzhen-Hongkong passenger dedicated line. Three independent fire fighting systems( i. e.，hydrant, water spray and fire extinguisher) were set simultaneously. To put out the fire not caused by oil, the water spraying system that is high efficient, water-saving and environmental protective was recommended, while the water sprinkle system was not recommended. The water supply system must meet the requirements of total water consumption, water quality, water pressure and the safety standards. The drainage system includes sewage drainage system and rainwater drainage system. Pump room is set at the lowest point of the tunnel for wastewater discharge from fire fighting, rinse and structure leakage. Both wastewater and rainwater were discharged into nearby water body.