Abstract Background Information literacy (IL) is vital in health education, yet studies indicate medical students' IL might be insufficient or deficient. This study aims to evaluate the impact of an integrated Evidence—based Medicine (EBM) course in improving information literacy (IL) skills among Chinese undergraduate and postgraduate medical students. Methods This study included 5—year and 7—year undergraduate students as well as postgraduate students majoring in clinical medicine from West China School of Clinical Medicine at Sichuan University who took the EBM course for the first time between January 2010 and December 2010 and participated in all sessions of the course. This study would employ a pre-and post-course comparison method to assess the impact of the integrated EBM course on the IL across different academic stages of Chinese medical students, in order to offer new and reliable strategies for the improvement of medical education of IL. The study incorporated an Evidence—Based Medicine (EBM) course intervention, followed by a comprehensive assessment of its impact. The course impact is defined as the alterations in students' self—perceived Information Literacy (IL) competencies, measured by the differences between pre—and post—course self—evaluations, along with the objectively demonstrated evidence application skills as reflected in the teacher—graded reports. Specifically, the evaluation of impact contains two parts: 1) subjective assessment, which was students' self-assessments of IL (information acquiring competency, information processing competency and information utilizing competency), conducted before and after the EBM course; 2) objective assessment, which was a teacher's assessment, conducted by having each student submit an evidence-based medical record report after the EBM course, and then the teacher assigning grades based on the records. Results A total of 288 medical students participated in the intervention course, including 5-year undergraduates (n = 106), 7-year undergraduates (n = 57) and postgraduates (n = 125). 1) Information acquiring ability: after the course, students demonstrate a more proactive and enthusiastic inclination towards acquiring information. Their capabilities and expertise in information gathering have notably improved. 2) Information processing ability, exhibited by a 9.7% increase in the number of students who can differentiate types of information (p