, Objective: To examine the relationship between patients’ treatment outcome expectation and a set of socio-demographic factors, clinical course variables, symptom severity, health locus of control, and Temperament and Character Inventory (TCI) dimensions. Method: Logistic regression analyses were performed on data collected at screen and baseline interviews from 45 participants enrolled into one of two randomized placebo controlled antidepressant trials. Results: Participants with high outcome expectations reported shorter depressive episodes and scored lower on Harm Avoidance (TCI). The data also suggest that external locus of control, gender, ethnicity/race, employment status, and the dimension of self-directedness (TCI) may have a role in shaping treatment expectation. Conclusion: Depressed patients’ treatment outcome expectations were found to be associated with depression characteristics, personality traits, locus of control, and certain socio-demographic factors. If these findings are replicated, this information can be used to identify individuals needing additional interpersonal support or motivation at the onset of treatment.