With the increasing demand of users for high-quality video content, medium and long video has become an important position for publishing institutions to conduct brand communication and product promotion. This paper takes publishing institutions’ bilibili accounts as the research subject. The data is collected in bilibili video data analysis platform "new station data", through the octopus network crawler tool for initial data capture, supplemented by Python dynamic page analysis and structured storage, to ensure multidimensional coverage of UP hosts’ basic information, work data, and interactive metrics. On the basis of data analysis, this paper identifies current situation and problems of publishing institutions in account operation, content production, user maintenance and other aspects. From the perspective of the content operation of publishing institutions, the head account has a monopoly advantage. There are two main modes of video content production: independent creation and cooperative creation. The video types are mainly knowledge science, including book publicity, interactive communication, cultural activities and other types. Although publishing institutions have made various attempts and explorations in the operation of medium and long video content in recent years, they also face many challenges.Most institutions lack the accurate positioning of the account, and lack the personalized image positioning. There is a structural contradiction between resource input and output in video content production, and some accounts are not updated for a long time, resulting in users' inability to form stable content expectations. Videos lack interactive design, and user participation is weak. Most publishing institutions rely on traditional business models and lack diversified realization paths such as membership subscription and knowledge payment. Based on the above analysis, publishing institutions should accurately position the brand image by combining the platform culture and user preferences. Through the production of serialized videos to form a stable user cognition path, and strengthen the professional image and brand recognition of publishing institutions. Establish a user growth system, set up a hierarchical system, and build a tribal community. Publishing institutions should create the mode of "deep creation + light marketing", realize brand communication and commercial transformation with the help of community ecology, and explore the collaborative mode of in-depth content creation and flexible commercial marketing. Medium and long videos enable more systematicprofessional and continuous knowledge content creation and dissem ination, which can make up for the shortcomings of fragmented and superficial short video operation, while fulfill the sophisticated demand of users for high-quality video. In the future, the fielid of medium and long video is expected to become a new growth point of content operation, brand communication and product promotion in the publishing industry.