The aim of this study was to identify and assess factors associated with nurse anesthetist competency in Finland, South Korea, Taiwan, and the United States. A cross-sectional design was used. The Anesthesia Nursing Competence Scale consisting of seven competencies was utilized: ethics, patient risk management, technological skills, collaboration, medication, optimizing anesthesia care, and anesthesia knowledge (0 = not competent at all, 10 = excellent competence). The data were collected via an online survey (N = 582) in 2024. Data analysis included correlation tests, t-tests, and linear regression analysis. The highest-rated competencies varied by country: collaboration in Finland (9.31 ± 0.68), medication in Taiwan (9.01 ± 1.19), and ethics in the United States (9.58 ± 0.84). However, anesthesia knowledge was the lowest-rated competency across all countries. Age, educational level, and work experience showed a positive correlation with competency and education level was identified as the most important factor influencing anesthesia nursing competency. Assessing these competencies as outcomes of nursing education in an international context remains crucial for promoting global standards in the education and practice of nurse anesthetists. Strengthening international collaboration in anesthesia nursing education and establishing standardized competency assessments could further promote high quality practices and ensure quality patient care.