Background: Childhood obesity is a global public health problem, being one of the risk factors for developing serious health problems in subsequent years. The objective of the study was to determine the relationship between neck circumference and anthropometric indices to assess obesity in schoolchildren. Peruvians from public educational institutions in Peru. Methods: Correlational type study in which anthropometric indices and their relationship with the Neck Perimeter (PC) were analyzed as a possible index to evaluate obesity in Peruvian schoolchildren. The data was collected in two public educational institutions (initial and primary) in the Villa El Salvador-Lima district. A total sample of 178 schoolchildren from 3 to 14 years of age who met the study inclusion criteria was obtained. Results: 81.8% of women are short, and 68.8% of men are at very high risk (visceral obesity) in relation to BAP for age. The correlations of the Spearman coefficients for both sexes established the best relationship between the PC and the PAB showed a direct and significant association (p <0.01) in women (r = 0.808) and men (r = 0.787), in comparison with the IMC and IPABE. Conclusions: The PC could be used as a simple, inexpensive and non-invasive measurement for the evaluation of obesity in Peruvian schoolchildren.