Background <p>Clinical reasoning competency is essential for patient safety. Nursing interns, in transition from students to professionals, are particularly vulnerable to errors. This study identified distinct profiles of clinical reasoning among nursing interns, described their characteristics, and examined factors associated with profile membership.</p> Methods <p>A multicenter cross-sectional study was conducted using convenience sampling. An online survey was administered to 1,185 nursing interns from 15 institutions across China. Latent Profile Analysis was used to categorize interns based on their scores on the four subscales of the Self-Assessment of Clinical Reasoning and Reflection scale and the total score of the General Self-Efficacy scale. The latter was included as a key psychological component integral to the development and manifestation of clinical reasoning competency. Differences across profiles were analyzed using ANOVA, chi-square tests, Kruskal-Wallis H test and multinomial logistic regression to explore associated sociodemographic and perceptual variables.</p> Results <p>Using latent profile analysis based on self-report scales, this study identified three distinct competency profiles. The “foundational competency group” (24.6%) scored lowest on clinical reasoning subscales and self-efficacy, yet showed a modest positive inclination towards reflection. The “advanced competency group” (14.9%) demonstrated the highest scores in clinical reasoning and self-efficacy but had relatively lower reflective scores. The “transitional competency group” (60.5%) exhibited moderate and balanced scores across all competencies. Multivariable regression analysis revealed that gender, educational level, choosing the field out of interest, willingness to participate in future training, and patient safety perception were significantly associated with profile membership among the interns (<i>p</i> &lt; 0.05). A higher level of patient safety perception was strongly associated with higher odds of belonging to the “advanced competency group” (OR = 1.364, 95% CI: 1.321–1.409).</p> Conclusions <p>Clinical reasoning competency among nursing interns demonstrates heterogeneity, with three distinct profiles. Patient safety perception is strongly associated with advanced competency. These findings provide a basis for understanding competency diversity and suggest that tailored educational strategies may support the development of clinical reasoning. Due to the cross-sectional design and self-reported data, findings represent associations, not causal relationships.</p> Trial registration <p>Not applicable.</p>