The objective of this work was to determine the osmolality of beverages frequently consumed by children and adolescents due to the scarce information available in our country. The samples were grouped as follows: milks; refreshments; beverages based on fruits, vegetables, cereals, and tubers; sport drinks; energizing drinks; oral rehydrating solutions; reconstituted drinks and infusions. A vapor pressure digital osmometer was used, five samples of each beverage from different lots were analyzed. Four osmolality determinations were made on each sample and the average of such values was calculated. When the variation coefficient of the osmolality measurements of the five samples was higher than 10%, five additional samples were analyzed. As many samples as possible were used with breast milk in the time period of the study. Osmolality averages, standard deviation, and the osmolality confidence intervals (95% reliability) were calculated. The osmolality (mmol/kg) of breast milk and that of cow milk were between 273 and 389; refreshments, white, black and flavored colas, and malts ranged between 479-811; and soda and light drinks: 44-62; fresh fruit and commercial drinks (coconut, peach, apple, orange, pear, pineapple, grape, plum, tamarind): 257-1152 and light juices: 274; sports beverages: 367; energizing drinks: 740; drinks based on vegetables and cereals: 213-516; oral rehydrating solutions: 236-397; reconstituted drinks: 145; infusions: 25. Beverages with adequate osmolality levels for children were: milks, light refreshments, soda, fresh and light juices, oral rehydrating, soy, and reconstituted drinks and infusions.