Smokers in several northern European countries and in the USA reportedly consume a less healthy diet than non-smokers. Little is known of the dietary habits of smokers in Mediterranean countries. The purpose of this study was to assess the diet-smoking relationship in a sample of Spanish employees. Four worksites were selected. The participation rate was 91.9% of a total number of 1,555 employees (1,193 men and 362 women) enrolled In the study. Each employee completed a self-administered food-frequency questionnaire and another questionnaire that recorded several cardiovascular risk factors including their smoking habits. Four occupational physicians recorded each subject's weight, height and alcohol consumption. High intakes of specifically targeted food items were used as the dependent variables. Crude and Mantel-Haenszel stratified odds ratios were computed for light (1–19 cigarettes/day) and heavy (>20 cigarettes/day) smokers. Multiple logistic regression models were fitted, controlling for age, sex, body mass index and alcohol consumption. Heavy smokers were more likely to have a higher intake of eggs, whole milk, pork, fried foods and legumes. Light smokers were less likely to have a higher intake of fruit than non-smokers. Unhealthy eating patterns and smoking are highly associated. Heavy smokers showed a less healthy dietary profile than both light smokers and non-smokers. Dietary recommendations should be included in the health promotion information addressed to smokers in Mediterranean countries.