Under the background of COVID-19, online living and flipping teaching is a new teaching mode,but how to improve its teaching quality is very important. The basic characteristics of blended learning courses was defined, and the online living and flipping teaching mode was put forward, the relationship between them also analyzed. On the base of the online living and flipping teaching practice of engineering economics course, combined with expert experience, the 27 influencing factors for the quality of it were identified. Based on the results of questionnaire survey, the 14 key influencing factors were identified. As a result, the strategies to improve the quality of online living and flipping teaching mode were put forward.