Historical and cultural films and TV movies focus on recording and presenting historical events, characters, cultural traditions and other contents through audiovisual means, and explore the cultural connotations and values behind them in depth. The study takes the film and television movie “30,000 Leagues in Chang’an” with the background of Tang culture as the case study object, analyzes the audience’s viewing and commenting data of the film and television, and analyzes the method of constructing the audience’s cultural memories by the historical stories and cultural characteristics in the film and television art. The study established the BERT-CCPoem-TextCNN text extraction model. On this basis, the audience’s online comments are mined from the online platform. Preprocessing is carried out in R language, the keywords in the comments are screened, and the theme keywords are cultural symbols such as poems, dresses, etiquette and so on are obtained after generalization. Then, the LDA theme model is used to analyze the direction of the audience’s emotions towards the film and television. According to the results of the theme, word speculation shows that what looks good and attracts the audience lies in the history and characters of films and televisions. The speculative value falls between 0.035 and 0.034. Finally, quantitative statistics are performed on the time changes of characters and events in films and television programs. The results show that the time interval of historical characters’ participation in historical events conforms to the power law characteristic, and the correlation between the importance of character nodes and the frequency of characters’ participation in events is stronger. This can serve as a reference for future work on historical themes in film and television art.