Adolescence is a period of transition or change between childhood to adulthood. One of the changes that occur is cognitive change, where there is a change in the ability to think. One of the factors that influence cognitive development is nutritional status. Nutritional status is one of the factors that influence adolescent intellectual development. Objective : The purpose of this study was to determine the description of the relationship between nutritional status to cognitive function in children's rapid growth phase of age 12-14 years in SMP Negeri 2 Mlati. Method : This research uses observational analytic research design with cross sectional study approach in teen age group 12-14 years old student of class VII and class VIII SMP Negeri 2 Mlati. Result : The number of subjects is 71 people. Primary data include of weight and height and secondary data are MMSE-Child and kuisoner. Data were analyzed by Chi-Square statistic test. Based on the measurement of Body Mass Index (BMI). It is known that most subjects have normal nutritional status of 32 people (45.10%), most have normal cognitive function that is as much as 63 people (88.70%). Conclusion : In this study found that, there is no significant relationship between nutritional status and cognitive function