In the era of intelligent media, exploring the impact of the information cocoon effect on user behavioral willingness in group polarization can provide suggestions for building a good ecosystem of social media platform. This paper was conducted based on the "stimulus-organism-response" framework and the theory of information ecology. Starting from the homogenization characteristics of the information cocoon, the study analyzed the mechanism of information cocoon formation and constructed a model of user group polarization under the information cocoon effect. The study then collected samples through questionnaire surveys and conducted empirical research through structural equation modeling. The results show that information homogenization, selective contact, inter-group emotion and social comparison frequency play an important role in the formation of users' behavior intention in group polarization. At the same time, user attitude polarization is also an influential factor of user group's behavioral willingness to polarization under the information cocoon effect.