AbstractUndernutrition is a silent emergency resulting from a combination of various social, economic, educational, demographic, and morbidity factors. This systematic and meta‐analytical review assessed the pooled prevalence of Composite Index of Anthropometric Failure (CIAF)–based undernutrition among under‐six years children in India. Articles were searched using Publish and Perish software and through reference exploration. The random effect model with the inverse method estimated the pooled prevalence (at 95% confidence interval, CI). Heterogeneity was tested through the I2 value and Q chi‐square. Subgroup analysis considered the National Food Security Act (NFSA), zonal distribution of studies, study location, and sample size. The pooled prevalence of CIAF‐based undernutrition among Indian under‐six children was 58% (95% CI: 0.54–0.62). After the implementation of the NFSA, the prevalence significantly dropped from 63% (95% CI: 0.58–0.67) to 56% (95% CI: 0.51–0.61). Undernutrition was higher in central and southern India (64%) but showed no significant difference between urban (58%) and rural (57%) areas (χ2 = 0.10; p = .76). The high I2 value (75%) indicated significant variation. Undernutrition remains a critical public health issue in India, particularly in central and southern regions. Enhanced screening, implementation, and monitoring of interventions are recommended.