BackgroundShared decision‐making is essential for improving infant prognoses. Medical staff should consider the effect of illness uncertainty and self‐efficacy on parents' perceptions of shared decision‐making.AimsThis study examined the impact of illness uncertainty and self‐efficacy on the perception of shared decision‐making among parents of infants in the neonatal intensive care unit.Study DesignA descriptive‐analytical cross‐sectional study design was used. Data were collected from April to June 2023. A total of 103 parents of infants admitted to the neonatal intensive care unit participated in this study. The participants used a self‐report questionnaire that included general characteristics of their infants, uncertainty of illness, self‐efficacy and perception of shared decision‐making. Data were analysed using descriptive statistics, independent t‐test, analysis of variance, Scheffe's test, Pearson's correlation coefficient and multiple linear regression.ResultsIllness uncertainty (r = −.659, p < .001, 95% confidence interval = [−1.209, −0.765]) was negatively correlated with self‐efficacy, and self‐efficacy (r = .255, p = .009, 95% confidence interval = [0.082, 0.569]) was positively correlated with the perception of shared decision‐making. Using multiple linear regression, the number of visits to the intensive care unit (β = −1.939, p = .015, 95% confidence interval = [−3.490, −0.389]) and parents' self‐efficacy (β = .271, p = .028, 95% confidence interval = [0.030, 0.512]) had a statistically significant effect on the perception of shared decision‐making, accounting for 11.9% of the total explanatory power.ConclusionsThe results support that higher self‐efficacy is associated with a higher degree of perception of shared decision‐making among parents of infants in the intensive care unit. Therefore, clinicians might support parents in taking a more active role in shared decision‐making by discussing available options with clinicians and reaching treatment plans together.Relevance to Clinical PracticeThe study suggests creating scales to assess nurses' participation in shared decision‐making and recommends educational programmes to boost parents' self‐efficacy with infants, significantly affecting perceptions of shared decision‐making.