Background: We investigated the magnitude of educational differences in lung and upper aero digestive tract (UADT) cancer mortality in France from 1990 to 2007. Methods: The analyses were based on census data from a representative sample of the French population. Educational level was used as the indicator for socioeconomic status. Educational differences in mortality from lung and UADT cancer were calculated among people aged 30-74 and by birth cohort. Two periods were compared: 1990-1998 and 1999-2007. Mortality rates, hazard ratios and relative indices of inequality (RII) were computed. Results: We found higher lung and UADT cancer mortality among those with less education. Inequalities in male UADT cancer mortality remained stable over time (RII(1990-1998)=0.21 (95% confidence interval 0.15-0.29); RII(1999-2007)=0.17 (0.11-0.26)) whereas inequalities in lung cancer mortality increased among the younger men (RII(1990-1998)=0.48 (0.28-0.83); RII(1999-2007)=0.16 (0.09-0.31)). Among women, inequalities in lung cancer mortality became apparent during the second period with higher mortality among those with less education. This trend was exclusively driven by the younger women, among whom inequalities reached about the same magnitude as among younger men (RII(1999-2007)=0.21 (0.08-0.56)). Conclusion: UADT cancer mortality rates strongly decreased over time for every educational level. This implies that the burden of health associated with socioeconomic inequalities in UADT cancer mortality decreased substantially. Inequalities in lung cancer mortality are increasing among the younger generation and are expected to increase even more. Differences in magnitude of inequalities among men and women may disappear in the coming decades.