<p>Amblyopia is the main cause of monocular vision loss in children. Early recognition and treatment are important to prevent vision loss. As public health awareness increases, short videos platforms like TikTok and Bilibili are increasingly being used to disseminate health information. However, due to the lack of peer review and supervision, short-video platforms tend to disseminate incorrect and incomplete health information. At present, the quality of videos on amblyopia has not been systematically evaluated. To evaluate the quality of videos related to amblyopia, this cross-sectional study used the Chinese term “amblyopia” as the search keyword to collect videos from TikTok and Bilibili. After applying exclusion criteria, 185 videos (94 from TikTok, 91 from Bilibili) were analyzed. Data on video length and characteristics, including engagement metrics (likes, collections, comments and shares) were collected. The assessment tools including the Global Quality Score (GQS), the modified DISCERN, the Journal of the American Medical Association (JAMA) benchmark criteria and the Video Information and Quality Index (VIQI) were used to evaluate video reliability and quality. Through statistical analysis, the quality and reliability among two platforms, video sources, and video quality were evaluated. On the TikTok, videos were mainly uploaded by specialists with accounting for 71.3%. While on the Bilibili, videos were mainly uploaded by individual users with accounting for 45%. TikTok videos scored higher in quality (GQS: 2.862 ± 1.033; modified DISCERN: 2.277 ± 0.8848; VIQI: 10.88 ± 2.531) compared to Bilibili (GQS: 2.242 ± 1.089 <i>p</i> &lt; 0.0001; modified DISCERN: 1.846 ± 0.8154 <i>p</i> = 0.001; VIQI: 6.571 ± 1.910 <i>p</i> &lt; 0.0001). Specialist-uploaded videos performed notably better in quality, with GQS, modified DISCERN, JAMA and VIQI scores of 3(3–4), 3(2–3), 3(2–3) and 11(9–13), respectively. On both platforms, the topic of amblyopia treatment was the most frequently discussed one, while the topic of prevention received the lowest level of discussion. The TikTok videos demonstrated a significantly higher level of audience engagement compared to Bilibili. Correlation analysis revealed that there were strong correlations between interaction data, but interaction data had no correlation with GQS, modified DISCERN, JAMA and VIQI scores. On the whole, the user engagement and quality of TikTok are both higher than those of Bilibili. However, both of two platforms fall short in terms of the quality and reliability of videos related to amblyopia. The reliability of specialist-uploaded videos is higher. This might be because they can provide information that is more valuable to the audience. The two platforms’ videos pay far more attention to the treatment of amblyopia than to its prevention. The proposed intervention measures include robust platform certification, active involvement of medical specialists in content creation, and enriching the video content.</p>