objective: this study aimed to determine the nutritional status of schoolchildren in public schools in porto velho, rond？nia, brazil, in relation to age, gender and sociodemographic features in a population of low socioeconomic status. methods: the sample comprised 1,057 schoolchildren of low socioeconomic status of both genders, aging from 7 to 10 years, selected by stratified random sampling by sector and purposeful sampling by group. sociodemographic data were obtained with a questionnaire. the schoolchildren were classified according to their weight-for-height into malnourished, well nourished and overweight/obese and according to their weight-for-height and height-for-age into well nourished, severely malnourished, chronically malnourished or formerly malnourished. results: there was no significant difference between males and females for weight and height. in relation to weight-for-height alone, 86.0% were normal, 4.0% were malnourished, 7.0% were overweight and 3.0% were obese. in relation to weight-for-height and height-for-age, 89% were normal, 2.5% were acutely malnourished, 7.0% were formerly malnourished and 1.5% were chronically malnourished. conclusion: the prevalence of malnutrition or overweight/obesity was low among elementary schoolchildren of low socioeconomic status in public schools of porto velho, rond？nia, brazil. these data can be compared with data from other brazilian cities and regions.