Omicron mutated virus set off another wave of climax, disrupting people's recovery life, and making the tourism and leisure industry worse again; The competitive and cooperative relationship between online travel agents and the hotel industry has brought a certain source of customers and traffic to the tourism industry. This study takes Guangdong C hotel as a case to explore the dependence of the case on the competitive and cooperative marketing of online travel agents and the transformation results of direct customers. There are three research results. Firstly, hotel C has a single marketing method for OTA. It is suggested to improve the direct sales channel interface and mark it clearly and concisely. Secondly, the transformation effect of OTA direct customers is not significant. It is suggested to formulate a reward mechanism, increase Ctrip's high-quality comments and enhance the transformation effect of direct customers. Finally, efforts should be made to improve customers' loyalty to the store's direct sales channel rather than OTA. Through the single case analysis of hotel C, this study analyzes the use of online travel agents to improve the conversion rate and expand the source of tourists in the post epidemic era. In the post epidemic era, we still need to do the basic work of service. Only when the flowers bloom in spring can we enjoy the improvement of the conversion rate, enhance the effect of direct customer conversion, and expand the gourmet achievements of the source of tourists.