The association between snoring and myocardial infarction was studied in 1453 people of both sexes aged 20-70 years. The study was carried out in a population of 92,364 residents and the subjects were recruited using the Electoral Census. A questionnaire was sent to all participants, asking about snoring and cardiovascular risk factors. Hospital records were checked for the next 4 years to establish how many of them developed myocardial infarction. At the beginning of the follow-up study 39 patients were diagnosed with ischaemic heart disease. Of the other 1414 participants, 571 (40.4%) were snorers and 843 (59.6%) non-snorers. Twenty-one developed myocardial infarction in the snorer group and four in the non-snorer group. The snorer group presents an adjusted relative risk of myocardial infarction of 3.08 (95% CI 1.01-9.46) with respect to non-snorers. We conclude that snoring seems to be a potential risk factor for myocardial infarction.