The purpose of this study was to examine the relationship between various levels of education, personality traits (neuroticism, extraversion, conscientiousness, agreeableness, and openness to experience), personality trait changes over time, and use of mental health services among middle-aged women. The subjects were 1110 women from 40 to 60 years of age responding to the 2005 National Survey of Midlife Development in the United States (MIDUS). The study used logistic regression first to investigate the predictive value of varying levels of education and personality traits on use of services during the past 12 months. A second logistic regression was used to investigate personality trait changes (between 1995 and 2005) on use of services during the past 12 months. Change scores were calculated using the reliable change index (RCI). In the first logistic regression, neuroticism (OR = 1.82, p <.001) and openness to experience (OR = 1.51, p < .05) were associated with significantly increased likelihood of mental health service utilization among middle-aged women. Conscientiousness (OR= 0.65, p < .05), in contrast, was associated with decreased likelihood of use of mental health services. Education and use of mental health services were not significant in the logistic regression. The second regression using the RCI scores was not significant, most likely due to the lack of reliable change for any of the personality traits. The significant association between neuroticism and conscientiousness and the use of mental health services among middle-aged women replicated findings from the 1995 MIDUS survey. However, this is the first study to find significance with openness to experience and use of mental health services among middle-aged women. Implications and future research are discussed.