There is a growing concern surrounding the utility of medical content on social media. In this study, the popularity metrics and content quality of cardiac rehabilitation (CR) videos on YouTube regarding patient education were examined. Using the search key word "cardiac rehabilitation," we analyzed the 50 most relevant videos. Our video popularity analytics encompassed viewing rate, such as ratio, number of comments, and the video power index (VPI). We assessed content quality using the Global Quality Scale (GQS), the modified DISCERN questionnaire, Journal of the American Medical Association ( JAMA ) benchmark criteria, Patient Education Materials Assessment Tool for Audio/Visual Materials (PEMAT-A/V), and a novel tool, the Cardiac Rehabilitation Specific Scale (CRSS). Notably, 78% of the videos were uploaded by medical organizations. The average viewing rate was 4.6 views per day. There were positive correlations between the scores from different content quality scales. Median scores for the GQS, the modified DISCERN questionnaire, JAMA benchmark criteria, and the CRSS were 3, 3.5, 2, and 5, respectively. Mean PEMAT-A/V scores were 60.4% for understandability and 38.3% for actionability. Videos published by entities other than medical centers predicted lower CRSS and GQS scores. High JAMA benchmark criteria scores were negative predictors of VPI, view rate, and number of comments. Our findings suggest that CR-related videos on YouTube are characterized by low popularity, average content quality and understandability, but a lack of reliability and actionability. To ensure individuals seek accurate CR information on social media platforms, we recommend directing them to videos uploaded by medical centers.