With the rapid growth of short-video live streaming, algorithmic recommendation has become the core driver of traffic distribution on Douyin. Many brands now use entertaining livestream content to reduce the stiff, promotional feel of marketing and attract viewers. This paper focuses on Douyin livestreaming, employing literature review and case analysis as its primary methods. It mainly explores how recommendation algorithms affect brand content dissemination and analyzes effective strategies for brand entertainment communication. The results show that algorithms enable accurate audience matching via user tags and behavioral data, while entertaining livestream content tends to sustain traffic advantages. Nevertheless, problems such as content homogenization still exist. Brands need to combine algorithm rules to innovate entertainment forms so as to achieve better communication and marketing effects. This research enriches the theoretical framework for algorithm-driven brand livestream communication in China's short-video ecosystem and offers actionable suggestions for physical-goods brands to implement long-term entertainment livestream marketing on Douyin.