Background: Intestinal ultrasound (IUS) is a non-invasive tool for monitoring inflammatory bowel disease (IBD), offering high diagnostic accuracy and greater patient convenience than gastrointestinal endoscopy. The present study evaluated the feasibility of a mastery learning approach in Indonesia’s inaugural IUS workshop to enhance skill acquisition among physicians. Methods: A retrospective study was conducted on 37 physicians who participated in a two-day IUS workshop employing a mastery learning approach that included flipped learning, lectures, a pre-test, hands-on sessions with real-time feedback, and a post-test. Skill acquisition was assessed using standardized checklists for scanning the sigmoid colon and terminal ileum, with pre-and post-test performance evaluated against a minimum passing standard (MPS) established by expert faculties. Data was analyzed using SPSS with appropriate statistical tests to determine learning outcomes and effect sizes. Results: 34 out of 37 participants completed the workshop and skill assessment. Significant improvements were observed in both sigmoid colon and terminal ileum ultrasound scores after training (P < 0.001), with effect sizes of r=0.89 and r=0.86, respectively. The MPS was achieved by 67.65% of participants for the sigmoid colon and 50% for the terminal ileum. Conclusion: A mastery learning–based workshop significantly enhanced IUS skill acquisition among internists and gastroenterologists. Based on the MPS criteria, approximately one-third of participants would require additional training for sigmoid colon scanning, while about half would benefit from further training in terminal ileum scanning. © 2026, Indonesian Society of Internal Medicine. All rights reserved.