Hi Mom is a movie released in Chinese New Year with widespread publicity and well-known movie stars. It became one of the hottest films in the 2021 Spring Festival Movie. The film grossed more than $5 billion at the box office, which is undoubtedly a huge success. In addition to impressing audiences with a unique "family" storyline and a different narrative approach, the marketing and publicity strategies of a movie are also necessary. The research direction of this paper is mainly content and publicity. For example, the selling points and opportunities of films with a box office of more than 5 billion Yuan are worthy of deep analysis, especially the role production companies play and the way to implement early publicity and promotion. The research adopts qualitative analysis by using a case analysis. Comparing the early stage (before the movie is published), the middle stage (during the movie is released) and the late stage (after the movie is dropped), it is found that compared with the first two time stages, the late stage after the movie released is obviously short of play rate in video platform and click number in short videos. The theme of family films in Chinese film market is simple, and some films have some problems in late release. Some suggestions are continuing to promote the relevant elements, deepening the theme to impress the audience and promoting the marketing in more innovative ways.