Hypertension is a growing clinical problem in pediatric population. Also, the cause of hypertension is usually unknown and it may result from systemic inflammation related to tooth decay. To estimate the potential association in cross-sectional study between tooth decay and hypertension in children and adolescents. Study group-65 children diagnosed with primary arterial hypertension; control subjects-44 normotensive children. Blood pressure, dental examination, measurement of salivary cortisol, alpha-amylase, secretory IgA, and lysozyme concentrations were performed in all of the children. Hyper- and normotensive children had similar peripheral blood morphology and serum biochemical parameters, except of uric acid concentration, which was significantly higher in the study group (p=.047). Salivary evening concentrations of cortisol and alpha-amylase were significantly higher in hypertensive children (p=.002 and p=.004, respectively). Although 24-hr systolic blood pressure (SBP), including daytime and nighttime SBP, correlated with "decay," "microalbuminuria," "BMI," and "glomerular filtration rate" (r>.75, r>.7, r<.68, and r<.43, respectively), in multivariate analysis only "decay" was associated with hypertension both in children and in adolescents (p<.0001). Tooth decay in children/adolescents might be regarded as a potent trigger factor of hypertension in individuals in whom all other causes of secondary arterial hypertension have been excluded.