This meta-analysis had two objectives: (a) to aggregate data from studies that used hormone replacement therapy (HRT) and a quantitative measure of depressed mood in order to examine the effectiveness of HRT upon menopausal depressed mood; and (b) to review the methodologies of this literature base. The overall effect size for HRT was 0.68. This indicated that the average treatment patient had lower levels of depressed mood than 76% of the control patients. Analyses of specific hormone treatments suggested that (a) estrogen significantly reduced depressed mood (ES = 0.69); (b) progesterone alone, and in combination with estrogen, was associated with smaller reductions in depressed mood (ES = 0.39, ES = 0.45, respectively); and (c) androgen alone and in combination with estrogen was associated with greater reductions in depressed mood (ES = 1.37; ES = 0.90, respectively). In summary, HRT appeared to be effective in reducing depressed mood among menopausal women. The methodological review indicated that most studies used adequate sample sizes, controlled research designs, random assignment, double-blind treatment manipulations, and valid and reliable measures of depression. Limitations in the interpretation of these results are discussed and recommendations for improved methodology are provided.