Most of the studies of inequalities in mortality carried out in Spain have been ecological, due to the di culty of obtaining good quality socioeconomic information at individual level. The objective of this study was to describe inequalities in mortality by social class, based on occupation, among men residents of Barcelona in 1993. A representative sample was obtained of men residents of Barcelona who died during the year 1993, aged between 15 and 65 years. It was a retrospective interview given to relatives of the deceased, or other closely related persons. The variables analysed were: age, education level, underlying cause of death, and social class based on occupation (manual and non-manual workers). Rates, relative risks (RRs) and their 95% con®dence intervals (95% CIs) are presented by age groups and cause of death. The main results show that among young people, the excess of mortality due to infectious diseases is notable (RR: 1.9; 95% CI: 1.6±2.2), and also due to external causes (RR: 2.1; 95% CI: 1.8±2.4) among manual workers with respect to non-manual workers, mainly due to AIDS and drug overdose. No signi®cant di erences were found in mortality due to tumours. For respiratory and cardiovascular causes, there is an increase in mortality in the less favoured social classes, as also occurs for mortality due to diseases of the digestive system, particularly among young manual workers, with an RR: 2.6 (95% CI: 1.5±3.6) compared to nonmanual workers. This study shows that it is necessary to continue exploring inequalities in health, but above all it is necessary to implement e cient preventive measures addressed mainly at young people in situations of disadvantage, in order to avoid the excess of avoidable mortality which is found.