Building on prior research of organizational demography, this study extends research on employee turnover to the organizational level by considering demographic compositions of a workforce that affect voluntary turnover: age and seniority, gender, occupation, and wage, plus the interaction effect between age/seniority and wage. It carries out empirical examination of a different cultural setting, using a sample of 3,796 firms in Taiwan. The results show that voluntary turnover rate is influenced by age and seniority heterogeneity, wage dispersion, and occupational differentiation. In addition, the effect of age and occupational heterogeneity is moderated by the wage dispersion within an organization, suggesting that the effect of organizational demography on employee turnover is cultural and context-specific.