We examined the clinical characteristics of post stroke depression (PSD) patients in a rehabilitation hospital. The subjects were inpatients at the Ibaraki Prefectural University of Health Sciences Hospital who had been diagnosed with stroke and admitted between May 2002 and January 2004. Of 123 patients enrolled, 18 were diagnosed with PSD. We investigated the clinical differences between PSD patients and non-depressed (ND) patients. There were no significant differences between PSD and ND groups in terms of sex, age, past psychiatric history, family psychiatric history, stroke diagnosis, or neurological symptoms. The scores of PSD patients on Zung's self-rating depression scale and the Hamilton depression rating scale were significantly higher than those of ND patients. Furthermore, the Activities of Daily Living measured by the Functional Independence Measure and cognitive function evaluated by the Mini-Mental State Examination of ND patients were significantly better than those of PSD subjects. These results suggest that the detection of PSD in stroke patients is important for promoting their rehabilitation and improving their Activities of Daily Living and cognitive function.