Introduction: Saliva is a complex body fluid secreted by both, the major and the minor salivary glands. It helps maintain oral health and an appropriate balance of the oral cavity. Due to its many advantages saliva has proven to be a highly valuable sample whose analytes change during various physiological and pathological conditions. One of the most important enzymes in the saliva is salivary alpha-amylase which prompt an interest as a stress indicator, but it also has a broad meaning in other clinical conditions. It is a metalloenzyme which hydrolyses alpha-1,4 glycosidic linkages of starch into glucose and maltose. Aim: The aim of this study was to determine the activity of the salivary alpha-amylase in a healthy adolescent population, to test the normality of distributing activity of the salivary alpha-amylase and establish the presence or absence of a statistically significant difference between male and female students in the measured activity of the salivary alpha-amylase. Matherials and methods: The sample of 194 students (70 male and 124 female) from high schools in Split was tested. The respondents underwent anthropometric measurements and saliva samples were collected according to the protocol for the passive, unstimulated secretion. Results: There was a statistically significant difference between male and female students in age, educational results, in all anthropometric measurements (height, weight, body mass index) and systolic and diastolic pressures. A statistically significant difference in the activity of the salivary alpha-amylase between male and female students was not determined. Activity measure of the salivary alpha-amylase for the whole sample does not demonstrate a normal distribution, while the activity in the male/female students sample does show a normal data distribution. Conclusion: It is necessary to conduct a more detailed research with more participants included. Key words: saliva, salivary alpha-amylase, activity, comparison