More and more companies are building brands through storytelling. However, few studies have divided brand stories into manufacturing stories and service stories, and explored the effect of brand stories with AI and human as the protagonist of the story. Based on fit theory, this paper discusses the interaction effect of brand story type (manufacturing vs. service )and story subject ( Al vs. human) on consumers' brand attitude and its internal influence mechanism. Through three experiments to test the research hypothesis, the results show that: for the manufacturing story, consumers have a more positive brand attitude towards the brand story with Al as the protagonist, while for the service story, consumers have a more positive brand attitude towards the brand story with human as the protagonist; the interaction effect of brand story type and story protagonist on brand attitude is mediated by brand story trust. This study enriches the relevant theories of brand story, and provides practical enlightenment for brand story marketing.