Abstract: During the Ming and Qing dynasties， there were frequent exchanges between China and Ryukyu. As an official channel established by China， the Chinese envoys crossed the East China Sea dozens of times and exchanged with each other. The natural environment of the ChinaRyukyu sea route is complicated. And the travel of the envoys had not only the danger of piracy， but also the danger of rough seas and broken ships. In order to cope with the risks caused by the natural forces during the voyage， the Chinese envoys took preventive measures such as improving the performance of the boat， improving navigation techniques， selecting talents and storing emergency supplies. While ensuring the safety of the voyages， these preventive measures also had a positive impact on the shipbuilding， and navigation technology， culture， and agriculture of Ryukyu， and promoted the development of the vassal relationship between China and Ryukyu.

Key words: envoy ships； seamanship； prevention strategy； ChinaRyukyu relations

摘要： 明清时期，中琉交往频繁，册封琉球使团作为中方构设的官方渠道，数十次横渡东海、互通往来。中琉航路自然环境复杂，使团出行既有海氛未靖之险，更有惊涛骇浪、船破人危之虞。为应对封舟航行中自然动力带来的风险，使团采取提升封舟性能、改进航海技术、遴选贤才能士、储备应急物资等措施预防。在保障航海安全的同时，这些预防措施也对琉球的造船航海技术、文化、农业产生积极影响，推进中琉两国宗藩关系的发展。