BACKGROUND: The resident selection process could be improved if United States Medical Licensing Examination (USMLE) scores obtained during residency application were found to predict success on the American Board of Anesthesiology (ABA) written examination (part 1). In this study, we compared USMLE performance during medical school to anesthesiology residency standardized examination performance. METHODS: Sixty-nine anesthesiology residents' USMLE, ABA/American Society of Anesthesiologists (ASA) In-Training Examination, and ABA written board examination (part 1) scores were compared. Linear regression, adjusted Pearson partial correlation, multiple regression, and analysis of variance were used to cross-correlate pre-residency and intra-residency scores. Residents' school of medicine location and year of graduation were noted. RESULTS: Both USMLE step 1 and step 2 Clinical Knowledge examinations correlated significantly with all intra-residency standardized tests. Averaged step 1 and step 2 USMLE score correlated to ABA written examination (part 1) score with a slope of 0.72 and r of 0.48 (P = 0.001). CONCLUSIONS: The USMLE is a significant predictor of residency ABA/ASA In-Training Examination and ABA written examination performance in anesthesiology. Our program has significantly increased its average written board examination performance while increasing the relative importance of USMLE in resident selection.