Background <p>With the increasing public awareness of health, TikTok and Bilibili have become the domain source of short-video platforms for health-related information. This study aims to investigate the quality and reliability of short videos about endometrial cancer on two platforms.</p> Methods <p>This cross-sectional study was conducted on TikTok and Bilibili to evaluate short videos related to endometrial cancer. The two platforms were searched using the term ‘endometrial cancer’ from 15:00 to 22:00 on 29 September 2025. The quality of related information was assessed by the Global Quality Score (GQS) and the modified DISCERN score (mDISCERN), and analyzed by descriptive statistics, inter-group comparison, and correlation analysis.</p> Results <p>200 initial endometrial cancer-related videos were searched, and finally, 174 videos were included from TikTok and Bilibili. The GQS and mDISCERN scores of both platforms were low (median 2/5), and the median(Q1-Q3) duration of these videos was 80&#xa0;s (46.50-144.50), and the duration of Bilibili videos was longer (111 s to 63&#xa0;s, <i>P</i> &lt; 0.001). The engagement with TikTok videos was relatively high (median likes: 1342 to 6, <i>P</i> &lt; 0.001). Expert-uploaded videos were longer than those from other origins (median 109&#xa0;s) and of better quality (median mDISCERN 3/5, <i>P</i> &lt; 0.001). The quality component was positively associated with the duration of short videos(<i>r</i> = 0.42–0.46). The five major dimensions of health demonstrated “fragmented content and insufficient depth”: the highest coverage rate of symptoms was 36.2%, while the lowest coverage rate of prevention was 3.5%; the coverage rates of etiology, diagnosis, and therapy were all below 20%.</p> Conclusions <p>Significant quality gaps exist in endometrial cancer videos. To enhance the structure and completeness of health information, professional participation should be strengthened in the future.</p>