The general objective of this research study was to determine the relationship between personal variables (age, sex, personal hygiene, breastfeeding, complementary feeding, vaccination), environmental variables (water consumption, solid waste management, excreta disposal, overcrowding) with diarrheal disease in older infants, cared for in a Health I – 3 Iquitos, 2023 establishment; It was a descriptive, correlational study, non-experimental design, we worked with a sample of 148 older infants, the technique was the interview and the instrument was a data collection sheet. To test the hypothesis, chi2 was used with a significance level α ≤ 0.05. The results were: there is a significant statistical relationship between vaccination (p=0.005), water consumption (p=0.001) and overcrowding (p=0.048) with diarrheal disease in older infants; There was no statistically significant relationsh...