OBJECTIVES: The prevalence of constipation is high after stroke. Multiple factors such as long-term bed-ridden status, comorbidity, medical illnesses are combined in this condition. However, the change of bowel movement during the early stage of stroke remains uncertain. METHODS: Patients with first stroke who admitted in a single institute from 2008 to 2009 were reviewed retrospectively and 36 patients were enrolled. As a control group, 47 consecutive orthopedic patients needing bed rest without surgery in the same period were enrolled. Data of stroke associated factors, frequency of BM (bowel movement) during 5 weeks, use of gastrointestinal medications, and outcomes were collected from the medical records. RESULTS: The cumulative incidence of decreased (<3/week) and severely decreased BM (<1/week) were 80.6% and 69.4% in stroke patients and 53.2% and 14.9% in control group (P<0.05). The cumulative incidence of increased BM (>3/day) was 38.9% in stroke and 14.9% in control group. In acute stroke, 58% of patient showed severely decreased BM in first week, and the proportion was rapidly decreased below 15% from second week. However, laxative use increased with hospital days. The occurrence of severely decreased BM in stroke patients was associated with National Institutes of Health Stroke Scale (NIHSS; P=0.004). Severely decreased BM was not associated with poor outcomes including death, morbidity, and stroke recurrence. CONCLUSION: Decreased BM is common in acute stroke. The occurrence of severely decreased BM is associated with NIHSS. However, the severe manifestation occurred mainly in the first week, and considered to be well controlled by laxatives.