ABSTRACT: The main objective of this research was to determine the relationship between the level of caries and bacterial plaque in public and private institutions of the canton of Riobamba in the year 2021; the same one had a mixed cross-sectional, observational and descriptive approach. The type of sample consisted of 100 students, 100 parents and 12 teachers from Unidades Educativas "Camilo Gallegos Toledo", "Carlos Cisneros" and "José María Román". The techniques used for data collection were observation and test with their respective instruments, the clinical history, and the questionnaire. Data processing showed that 74% have a low caries index, 18% medium, and only 8% high. Regarding the O'Leary plaque index, 57% have questionable oral hygiene, 30% poor, and 13% acceptable. A statistically significant relationship was found between the ceod-CPOD index and the level of knowledge of the students (p=0.019) and with the level of education of the mother of the family (p=0.006). In conclusion, the rate of caries and oral hygiene depends on the level of knowledge in oral health that the student has.Achig Guanoluisa, Y (2022) Nivel de caries y placa en escolares. Sector 2. Riobamba, 2021 (Tesis de pregrado) Universidad Nacional de Chimborazo, Riobamba, Ecuador.UNACH,Ecuador