The purpose of this study was to assess whether the presence and severity of psychiatric symptoms in stroke patients correlate with their length of stay (LOS) in a rehabilitation unit, with special emphasis on the role of negative symptoms (NS). Twenty-three stroke patients, consecutively recruited from the inpatient rehabilitation unit, were evaluated on admission with the Mini-Mental State Examination (MMSE), the Positive and Negative Symptom Scale (PANSS), the Hamilton Depression Rating Scale (HDRS), the Scale for Assessment of Negative Symptoms (SANS), and the Functional Independent Measure (FIM). NS scores significantly correlated with LOS, with SANS total score being the most informative, and the attentional impairment subscale the least. The group of patients with pronounced NS stayed in the hospital twice as long as patients with the score on the NS subscale of PANSS below 16. These two groups did not differ in their cognitive performance or in the positive symptom subscale of PANSS scores. Total FIM score on admission was lower and HDRS scores higher in patients with pronounced NS. However, these differences, unlike those of LOS, have not reached statistical significance. The presence and severity of NS in stroke patients are associated with a longer hospital stay. Identification and treatment of NS might lead to a faster discharge from rehabilitation unit.