The sensory upgrading facilitated by live platforms, such as YouTube Live, Twitch, and Periscope, can facilitate much better interactions and understanding between a product, its brand, and the user. The question of how to enhance sustainable marketing effects using exterior design is currently a major topic in the live streaming marketing sector. The effect of the exterior design of a live platform on the impulse purchases of its consumers has rarely been discussed by academic research. Accordingly, based on the theory of self-determination, this study explored the direct effects of exterior design, self-efficacy, psychological ownership, and impulse buying by using multiple linear regression, and examined the indirect effects of these variables using the structural equation model. In this study, 534 samples were collected from live consumers, and our hypotheses were verified by employing hierarchical regression. As revealed from the results obtained, the self-efficacy and psychological ownership exhibited by consumers exerted synchronous and chain mediating effects on the relationships between the exterior design of the platform and consumer impulse buying. To enhance this marketing effect, live platforms should focus on designing pleasant exterior clues, creating a better psychological atmosphere, and the enhancement of consumers' self-efficacy.Sustainability 2020, 12, 2406 2 of 16 real-time games, special events, and behind-the-scenes tours [4,5]. The live streamer, acting as the content creator of the streaming platform, is capable of uploading real-time video and audio (e.g., video games, talent shows, and daily life records) to satisfy the diversified needs of users [6]. In other words, flattened, equal, and real-time communication can be achieved between users and the live streamer through the live platform, as well as among users, thereby narrowing the distance between companies and individuals.The growing popularity of live platforms has also had certain effects on the existing marketing methods and user buying behavior of companies [7]. Data show that in 2017, 48 percent of internet users in the USA watched live streaming at least once a week [8]. As suggested by a report from the China Internet Information Center, the number of live streaming users in mainland China reached a total of 433 million in June 2019, making up 50.7% of China's entire internet population. With such a considerable number of users, live platforms have started reshaping marketing channels and enhancing marketing effects. The global live streaming market was predicted to expand from US$30.29 billion in 2016 to US$70.05 billion by 2021 [9]. During the "618" period in 2019, Taobao's live streaming led to commodity sales worth CNY13 billion. Compared with the conventional marketing channels, live platforms have a more thorough impact on consumers' purchasing behavior. Thus, since live streaming is such a novel and powerful marketing tool, the questions of whether consumers engage in impulse buying after being exposed to live streami...