This study determined which variables affect women's positive mood state during the menopausal transition using nine prospective annual assessments of a population based sample of 267 Australian mid-aged women. Longitudinal data analysis carried out by analysis of covariance on Summary Statistics found that positive mood scores remained stable over time and were not related to natural menopausal transition, age, or education. In the early phase of the menopausal transition, positive mood was adversely influenced by baseline interpersonal stress (p = .009) and negative attitudes to aging (p = .026). The most important predictor of positive mood at the phase of late peri-/ postmenopause was positive mood in the premenopause (p = .000). Other factors affecting positive mood in the late peri-/postmenopause were changes in dysphoric symptoms (p = .000), major life events (p = .041), daily hassles (p = .014), marital status (p = .007), and work satisfaction (p = .001). Structural equation modelling found a goodness of fit index of .821.