This study investigated the psychometrics of the Self-Assessment of Nursing Informatics Competencies Scale for nursing students in undergraduate (n = 131) and graduate (n = 171) programs. The scale had a valid five-factor structure, accounting for 69.38% of the variance, high internal consistency reliabilities (0.96 for the total scale and 0.84 to 0.94 for subscales), and good responsiveness (standardized response mean = 0.99), as well as significantly improved scores in nursing students with diverse demographic and educational backgrounds after taking an informatics course. Our factor structure was similar to the original scale, differing slightly in four items’ loadings. This difference may reflect current informatics practice or the greater diversity of our sample. Further research is needed on the factor, data/information management skills, and related item loadings. This scale could be used to assess informatics competencies and develop educational strategies that prepare nursing students as informatics-competent graduates in information technology–rich environments.