The prevalence of snoring, overweight and systemic hypertension was estimated in a random sample of 4,064 Swedish men, aged 30-69 years. Of the responders, 15.5% complained of habitual snoring and 29.6% of occasional snoring. Although there was an age-related increase in the prevalence of snoring up to 60 years, habitual snoring was found to be mainly related to body mass index (BMI) (p less than 0.0001) but not to age. Altogether 299 men (9.3%) reported hypertension, 21.5% of whom were habitual snorers, compared with 14.9% of the non-hypertensives (p less than 0.01). The hypertensives were also more often overweight. Logistic multiple regression analyses showed that among subjects 40-49 years old there was an average increase in the predicted prevalence of hypertension from 6.5% among non-snorers to 10.5% of habitual snorers in the same weight group. For the whole study population, however, the increase was mainly dependent on age and BMI. Thus, the importance of habitual snoring for the prevalence of hypertension differs in various age groups.