PurposeRecently, short-form video apps, as a new form of social media, have attracted users and rapidly emerged by virtue of their personalized recommendation algorithms, interesting forms of live interaction, and diverse interactive functions, which may lead to excessive use. From the perspective of IT affordances, this study combines the cognitive-affective-behavioral model and perceived values theory to examine the formation mechanism of the excessive use of short-form video apps.Design/methodology/approachWe surveyed a total of 351 users who have used Tiktok, a typical short-form video app, and used their questionnaires to test the research model.FindingsSearching affordance has a positive impact on perceived information value and perceived entertainment value. Furthermore, meta-voicing, recommending, and livestreaming affordance have a positive impact on perceived information value, perceived entertainment value, and perceived social networking value, which also have a positive impact on negative affect anticipation. In addition, negative affect anticipation is significantly positively correlated with excessive use.Originality/valueIn terms of theory, this study introduces the theory of IT affordances and perceived values into the cognitive-affective-behavioral model, to the best of our knowledge, for the first time. Furthermore, it conducts situational research on the formation mechanism of excessive use of short-form video apps and makes up for the lack of studying of excessive use behavior from the perspective of technical factors.