Aiming at the problem that a single smart home interaction mode based on interface and voice hinders the user's natural experience, this paper explores a smart home design method based on multimodal information interaction to achieve a more natural and friendly user experiences of smart homes. Based on the multi-modal natural interaction characteristics of user daily life, this paper explores a smart home information interaction mode characterized by multimodality, constructs a multimodal information interaction design framework for smart home, and analyzes the elements, interaction process, modal organization, attention of multimodal information, modal density, modal structure configuration, etc. The multimodal information interaction of smart home realizes the initiative, sympathetic information acquisition and contextualized information analysis and feedback of the smart home system, which can improve the autonomy of the intelligent system, reduce the cognitive load of the user interaction process, and achieve a more natural, friendly user experience. In general, the smart home environment needs to change the traditional single human-machine system information interaction mode, and promote the optimization of the smart home use experience with multimodal information interaction.