Objectives: Immunization has been identified as a specific nutrition-related intervention to address the direct causes of stunting. This study examines the association between basic immunization status and stunting among toddlers in Indonesia. Methods: We conducted a cross-sectional analysis using data from the 2021 Study of Indonesia’s Nutritional Status. A total of 70 267 toddlers, aged 12 months to 59 months, were examined. Cox regression was employed to calculate adjusted prevalence ratios (aPRs) with their 95% confidence intervals (CIs). Results: The prevalence of stunting among children aged 12 months to 59 months in Indonesia was 23.1%, while 74.9% of children under 5 years old had complete basic immunization status. Multivariable analysis revealed a statistically significant association between basic immunization status and the incidence of stunting. Relative to toddlers with complete basic immunization, those with in-complete (partial) immunization were at a 1.18 times higher risk of stunting (aPR, 1.18; 95% CI, 1.15 to 1.22). Furthermore, toddlers who had not been immunized at all faced an even greater stunting risk (aPR, 1.27; 95% CI, 1.17 to 1.37). This association persisted after adjusting for variables such as maternal education, economic status, and the child’s birth weight. Conclusions: Basic immunization status influences the incidence of stunting in toddlers aged 12 months to 59 months. Thus, parents must ensure that their children’s immunizations are completed according to the recommended schedule. Additionally, it is crucial to increase parental awareness regarding health service utilization, disease prevention, and the nutritional needs of toddlers. © 2025 The Korean Society for Preventive Medicine.