During World War II, a large number of Japanese men were drafted in military service or forced to work for military factories. How could this massive wartime mobilization contribute to forming a stable postwar Japanese society? This paper explores the influences of wartime mobilization on career mobility of Japanese men, using 1955, 1965, and 1975 Social Stratification and Mobility surveys. This paper first attempts to reconstruct life history data of respondents that enable us to analyze the relations between wartime experiences and careers. The analyses of the life history data then revealed that there were clear age differences in wartime experiences among birth cohorts. Highly educated men of the 1916-20 birth cohort tended to be forced to work for military factories or drafted. After the war, they tended to switch workplaces more often and achieve better occupational status. In addition, multivariate analyses of occupational attainment indicated that educational levels and fathers' occupations strongly influenced patterns of occupational transitions from wartime to the postwar period among people who experienced wartime mobilization in their twenties or thirties. Using these results of analyses, this paper argues that the fluidity of highly educated men from wartime to the postwar period contributed to forming a stable postwar stratification system.