The paper aims to investigate how social media platform, rednote, in China, can influence the output complexity and creativity of Chinese second English learners. The author predicts that compared with traditional in-class learning environment, social media platforms like rednote can significantly increase Chinese English secondary language learners' output complexity and creativity. The author obtains the results from a real lab experimental with 100 participants recruited from college students. The participants were randomly assigned to two conditions: rednote and traditional classroom methods. Results indicate that the participants in the rednote condition significantly outperformed the control group of in-class condition in terms of their language complexity and creativity. The result of this paper proves that rednote, as a social media platform, has great potential as a language learning tool for second language learners. The paper also provides practical implications for educators and educational technology developers and identifies areas for future research.