Background: Informative narratives are texts that embed factual information in a story. They are often believed to increase not only text comprehension but also situational interest compared with expository texts. However, research regarding their impact on situational interest is missing. Aims: We examined the effect of informative narratives and expository texts on situational interest and how this impact affected text comprehension. Additionally, we investigated whether the learner-related factors individual interest, need for cognition, and need for affect moderate the relationship between text type and situational interest. Sample: Participants were 123 university students. Methods: In a randomized design, participants read either informative narratives or expository texts about biology topics. They completed measures of situational interest and text comprehension and questionnaires on need for cognition, need for affect, and individual interest. Results: The informative narratives led to a higher situational interest than the expository texts. Although situational interest and text comprehension were positively related, informative narratives did not lead to better text comprehension than expository texts. In fact, the positive effect of informative narratives on situational interest counteracted a negative direct effect on comprehension. Moreover, none of the tested moderator effects were significant. However, learners with higher need for cognition and higher individual interest developed a higher situational interest across both types of text. Conclusions: Overall, the findings suggest that informative narratives are useful to promote situational interest in science education, even when they do not enhance text comprehension compared with expository texts.