Recent studies of men have shown that job stress is important in understanding the occupational gradient in coronary heart disease (CHD), but these relationships have rarely been studied in women. With increasing numbers of women in the workforce it is important to have a more complete understanding of how CHD risk may be mediated by job stress as well as other biological and behavioural risk factors. The objective of this study was to examine the occupational gradient in CHD risk in relation to job stress and other traditional risk factors in currently employed women. We used data from the Stockholm Female Coronary Risk Study, a population based case-control study, comprising 292 women with CHD aged 65 years or younger and 292 age-matched healthy women (controls). An inversely graded association was observed between occupational class and CHD risk. Compared with the highest (executive/professional), women in the lowest occupational class (semi/unskilled) had a four-fold (95% CI 1.75-8.83) increased age-adjusted risk for CHD. Simultaneous adjustment for traditional risk factors and job stress attenuated this risk to 2.45 (95% CI 1.01-6.14). Neither job control nor the Karasek demand-control model of job stress substantially explained the increased CHD risk of women in the lowest occupational classes. It is likely that lower occupational class working women face multiple and sometimes interacting sources of work and non-work stress that are mediated by behavioural and biological factors that increase their CHD risk.