Abstract: Based on the CBTC system, the interconnection between intercity railways and urban rail transits is achieved through equipment compatibility, which is described in detail from four aspects: the design of interlocking system in the transition area, the compatibility of on-board equipment, the layout of track side equipment, and the handover of vehicle control rights. This scheme can realize the seamless switching of signal system without stopping in the transition area of intercity railway and urban rail transit lines. It is of great significance to the realization of interconnection and through operation of intercity and urban rail in the Greater Bay Area.