The purpose of this study was to determine whether the defense style of hospitalized depressed adults improved over the course of treatment. Thirty-one inpatients (24 women and 7 men) with an admitting diagnosis of major depression completed the 40-item Defense Style Questionnaire and the 20-item Center for Epidemiologic Studies-Depression Scale. Participants completed the Defense Style Questionnaire and the Center for Epidemiologic Studies-Depression Scale within 48 hours after admission and within 24 hours before or after discharge. The average admission and discharge Center for Epidemiologic Studies-Depression Scale ratings (+/-SD) were 41.93+/-9.93 and 26.45+/-12.19, respectively. The average hospital length of stay was 7.1+/-2.8 days. Two-tailed t-test comparisons of the Defense Style Questionnaire admission and discharge ratings showed significantly higher discharge mature ratings, significantly lower discharge immature ratings, and stable neurotic ratings. We concluded that for some depressed women and men, improvement in defense style can occur within days after the initiation of standard inpatient treatment.