This article uses the 1964 to 1992 March Current Population Survey data to examine cohort differences in men's late-life labor force participation for the 1895-1934 birth cohorts. Results using an age-period-cohort model indicate that a substantial portion of cohort differences may be attributed to changing levels of social security benefits, the proportion of workers receiving disability benefits, and the unemployment rate. The results also indicate lager cohort differences among Blacks and rural residents.