The invention discloses a system for docking an accident ship with a rescue ship in a terrible ocean environment and an implementation method. The system comprises a robot, a navigation positioning system, a cable laying system and a mother ship controller, wherein the robot adopts the two-section design of a front section and a rear section; the two sections are hinged by a waterproof steering engine; the walking of the surface of a hull is completed by using a magnetic track; underwater movements are completed by using two horizontal thrusters and two vertical thrusters; the navigation positioning system adopts a mode of combining two positioning modes, and the rescue ship is used as a core; the rescue ship locates the accident ship by using AIS (Automatic Identification System) radar, and locates the underwater position of the robot by a USBL (Ultra-short Base Line); the cable laying device consists of a shore-based cable laying device; cable laying equipment is provided with a separate servo driving function, and can be used for quickly releasing an umbilical cable of the robot, so that the influence of the cable on the robot is reduced. The system provides sufficient support for rescue work of the accident ship in the terrible ocean environment.