Researchers and international organizations frequently suggest that older women are disadvantaged in comparison with older men. This analysis of census and survey data from Thailand, however, indicates a far more complex association between gender and various aspects of aging. Through an examination of various demographic, economic, psychosocial, and health variables, it is found that older Thai women do face certain disadvantages compared to their male counterparts, including lower education and literacy, far higher levels of widowhood and living alone, and a lower likelihood of receiving formal retirement benefits. Older Thai men, however, face other disadvantages, including worse survivorship, a lower likelihood of receiving money from adult children, and a greater probability of financial problems. Our analysis provides some support for a life course perspective relating gender differences in old age to differences in earlier life experiences, roles, and reward structures. Also, marital status often mediates gender differences in well-being among older Thais.