BACKGROUND: Cardiopulmonary exercise testing (CPET) is conducted globally. On TikTok, CPET-related content serves as a key source of information for the public. However, the quality of these videos has not been systematically evaluated. This study aims to assess whether CPET videos on TikTok meet the informational needs of users. METHODS: A cross-sectional analysis was performed on TikTok videos about CPET in China. Video sources were identified and analyzed. Content evaluation focused on CPET principles, indications, procedures, and indicator interpretation. The reliability and quality of the videos were assessed using four standardized tools: modified DISCERN, Global Quality Scale (GQS), JAMA benchmarks, and Patient Education Materials Assessment Tool for Audiovisual Materials (PEMAT-A/V). Misinformation was summarized, and the relationship between video quality and characteristics was examined. RESULTS: Of the video sources, 43.8% were from physicians, 12.5% from nonphysicians, 12.5% from general users, 14.5% from news agencies, 12.5% from nonprofit organizations, and 4.2% from for-profit organizations. Median scores for modified DISCERN, GQS, JAMA, PEMAT-A/V understandability, and actionability were 1.00, 1.00, 2.00, 33.00, and 29.00, respectively. Videos by physicians had significantly higher modified DISCERN and JAMA scores compared to those by nonphysicians ( CONCLUSIONS: The quality and reliability of CPET videos on TikTok are uncertain, with many containing significant misinformation. This problem largely stems from content creators' insufficient understanding of CPET. To address this, implementing standardized training and certification is necessary. Videos produced by physicians generally exhibit higher quality, highlighting the importance of strengthening their leadership in CPET teams. Furthermore, social media platforms should work with CPET providers and video creators to develop a certification system for medical information. These steps could improve video quality, reduce misinformation, and promote accurate CPET knowledge, ultimately benefiting public health.