Fishery Internet of Vessels (FIoV) is the expanding application of Internet of Things technology in the fishery field. It plays an important role in fishery production, safety management, and marine scientific research. Aiming at the problem that most fishing vessels in China are small tonnage, low intelligent, and inability to realize Fishery Internet of Vessels, based on the diverse application scenarios and functional requirements of Fishery Internet of Vessels, a shipborne terminal system is designed and implemented based on the Fishery Internet of Vessels. The double-layer nested host design is adopted to realize the centralized access and processing of various types of sensors; the data compression and related data fusion are realized through the multi-sensor data fusion design; the automatic switching of real-time data transmission methods in different sea areas is realized through the adaptive communication switching design; based on the .NET development platform and Chromium kernel framework, the system software function is designed to realize the centralized processing and transmission of system data and other functions; the performance test of the system is completed by deploying fishing vessels for sea trials. The test results show that the system can support the access and data processing of 16 multi-source sensors, achieve a 78% data compression rate through data fusion, and meet the networking requirements of Fishery Internet of Vessels in the whole sea area through four types of communication modes. The system has complete functions, stable and reliable performance, and can provide support for the intelligent transformation of Chinese fishing vessels and the construction of Fishery Internet of Vessels.