Background: Eliminating the NIH funding gap among underrepresented minorities (URMs) remains a high priority for the National Institutes of Health. In 2014, the National Research Mentoring Network1 Steps Toward Academic Research (NRMN STAR) program recruited postdoctoral, early-stage and junior faculty to participate in a 12-month grant writing and professional development program. The expectation of the program was to increase the number of grant submissions and awards to URM researchers. Although receiving a grant award is the gold standard of NRMN STAR, instilling confidence for postdocs and early-stage faculty to submit an application is a critical first step. Based on our previous study, a sustained increase in trainee self-efficacy score over a 24-month period was observed after completing NRMN STAR.Methods: The current study sought to determine the association between self-efficacy score and grant submissions among two cohorts of trainees. Grantsmanship Self-Efficacy was measured using a 19-item questionnaire previously described by and used in our own work, which was originally adapted from an 88-item Clinical Research Appraisal Inventory.2 A binary variable was created to identify trainees who submitted an initial or revised proposal vs those who abandoned their proposal or were still writing. Trainees were assessed prior to and following program completion with subsequent assessments at 6 and 12 months beyond participation.Results: As of June 20, 2019, 12 of the 21 (57%) trainees had submitted a grant proposal (eg, NIH, other federal or non-federal grant). For every point increase in 12-month post assessments, Grantsmanship Self-Efficacy scores across all domains had a 44% higher prevalence of submitting a grant after controlling for race, sex, education level, academic rank, research experience, duration of postdoctoral training, institution type, and NRMN STAR cohort. Conclusions: Our findings demonstrate that NRMN STAR had a positive impact on trainees’ confidence in grant writing and professional development activities, which resulted in higher grant submission rates.Ethn Dis. 2021;31(4):559-566; doi:10.18865/ed.31.4.559