Introduction: Language discordance among health care providers and patients has been shown to result in poor patient outcomes. Health care providers who identify as being proficient in the native language of their patients may decline the use of professional interpreters due to their self assessment of language proficiency. More information is needed about whether providers who speak Spanish are proficient in medical Spanish. This study measured medical-Spanish language proficiency among nursing students. Methods: A quantitative pretest posttest evaluation (N = 30) at a large private university in the northeastern U.S. compared student and faculty assessment of student language proficiency after taking a medical-Spanish course using the Interagency Language Roundtable (ILR). T-tests compared student's final, self-assessed ILR scores with faculty's final ILR scores. Results: A significant difference was noted between students' self assessments and faculty assessments of student language proficiency (Rater 1: t(29) = -2.660, p = 0.013; Rater 2: t(29) = -2.693, p = 0.012) with high interrater reliability (kappa = 0.875). There was a significant difference between students' self-assessment of language abilities before and after the course (t(29) = -3.694; p < 0.001). Conclusion: Objective assessment of medical-Spanish language proficiency following a medical Spanish course may more accurately measure proficiency than self-assessment alone.