This study was conducted to investigate the effect of web-based teaching on paediatric nursing internship students' self-confidence and anxiety levels in the clinical decision-making process. The study sample consisted of 61 students who received internship training in the Pediatric Nursing department. There were 30 students in the control group and 31 students in the experimental group. Data were collected using a sociodemographic form, and nursing anxiety and self-confidence levels were measured using a clinical decision-making scale. The data were analysed using a t test, a Mann-Whitney U test, a correlation analysis, and a regression analysis, along with power and effect size. The self-confidence scores of the experimental group were higher than the scores of the control group (p < 0.05), and the anxiety scores of the experimental group were lower than the scores of the control group (p < 0.05). The web-based training program accounted for 17.8% of the change in self-confidence and 12.8% of the change in anxiety level. Therefore, the web-based training program was effective in increasing nursing students' self-confidence levels and decreasing their anxiety levels in the clinical decision-making process.