Background <p>Rare diseases (RDs) affect 10% of the global population but have inadequate medical resources. Early detection and treatment are crucial, yet many emergency physicians lack awareness of RDs. This study aims to evaluate the effects of continuing medical education (CME) on the knowledge and attitude of emergency physicians.</p> Methods <p>This retrospective study was conducted from April to June 2023, involving 218 Chinese emergency physicians. The online questionnaire consisted of four groups and 30 questions, covering demographic data, knowledge, and attitudes regarding RDs. Respondents were divided into two groups based on their recent CME training experience with RDs.</p> Results <p>Two hundred and eighteen emergency physicians completed the questionnaire, of which 108 received RD CME training and 110 did not receive RD CME training. Most respondents (98.2%) felt their knowledge about RDs was insufficient. The CME training group showed increased awareness of RD incidence (<i>p</i> = 0.047) and improved case analysis after training, but only slight improvement in knowledge of RD professional websites. Among the CME training group, CME was identified as the most prominent avenue for acquiring knowledge about RDs, with 72 respondents (66.7%, <i>p</i> &lt; 0.001). In contrast, in the non-training group, clinical work was identified as the primary source of learning, with 47 respondents (42.7%, <i>p</i> &lt; 0.001).</p> Conclusion <p>Emergency physicians generally lacked knowledge about rare diseases. CME training can improve their awareness and knowledge of RDs.</p>