The objective of this article is to describe trends in lung cancer mortality among employed men over the period 1976–2005, by industry sector and socio-occupational category. This study was conducted as part of the Cosmop surveillance program. The socio-occupational data were drawn from the DADS panel compiled by INSEE. For each individual in the panel, vital status was tracked through 2005 by linking the data to the national registry of medical causes of death managed by the Inserm Center for Epidemiology of Medical Causes of Death. The results show significant disparities in mortality among employed men across different economic sectors. Over the entire 1976–2005 period, rates varied by a factor of two between the sector with the lowest rate—education—and the sector with the highest rate—construction—with 43 and 98 deaths per 100,000 person-years, respectively. While overall, as in the general population, mortality rates increased between the 1976–1985 and 1986–1995 periods before declining over the 1996–2005 period, certain sectors stand out due to an increase in mortality throughout the study period. This is particularly true for construction, education, and public administration. Continued monitoring of cancer mortality by occupational sector will help identify sectors where specific prevention measures should be implemented, particularly regarding smoking for lung cancers.