By using the methods of system overall assessment and accident boundary area assessment, the code rules of fire accident and water inflow accident boundary area are analyzed, and the design scheme of electric propulsion system is evaluated for safe return to port. Taking a cruise as an example, this paper analyzes the configuration scheme, equipment layout, cable selection and direction, and system correlation of its electric propulsion system, verifies whether the design scheme of electric propulsion system meets the requirements of safe return to port, and provides guidance for the SRtP assessment of other systems of cruise.