Abstract: With more and more tunnels containing gas, it is crucial to control the risks in the construction of gas-rich tunnels. Using the construction of a gas-rich tunnel group encountered in Lot LYS-10 of the Lanzhou-Chongqing railway as an example, the construction characteristics and grading of gas-containing tunnels are presented, and such aspects as gas predicting, testing and monitoring, ventilation, mechanical equipment, and power supply configuration are studied. The features and hazards concerning gas-rich tunnels are discussed, and relative countermeasures are proposed.