The flood-proof sealed partition device for underground structures in this invention includes a power control system, door body, door frame, safety devices, etc. The power control system of this device mainly consists of a double hook electric hoist and PLC controller. The double hook electric hoist system is installed at the bottom of the reinforced concrete beam on the top of the tunnel, and its hook pulley group is fixed to the top or secondary beams of the gate with bolts to save height space. To ensure safety, the device can be equipped with three sets of safety mechanisms: mechanical automatic lockers on both sides of the lower part of the door body, mechanical automatic lockers on both sides of the upper part of the door body, and an electrically controlled mechanical locker on the lower part of the back of the door body. This invention effectively solves the emergency isolation protection problem when water disasters occur in underwater tunnels crossing rivers under complex conditions such as subway traction systems and track systems. It plays an important role in eliminating potential human security hazards in underground rail transit cross-river projects. Further improving the city's disaster prevention and resistance capabilities has played a positive and important role.