Introduction: CPT-11 induced diarrhea reduces patient compliance, lowers quality of life, and can be potentially life threatening. Loperamide is effective in the majority of cases of CPT-11-induced diarrhea. However, the case of advanced gastrointestinal cancer where oral administration is difficult. We adapted octreotide for use in a case of CPT-11-induced diarrhea where oral administration was difficult due to digestive tract stenosis. Case Report: A 61-year old man was diagnosed with advanced gastric cancer. He was treated with CPT-11 100mg/m² weekly for three weeks followed by a 1-week rest. CPT-11-induced diarrhea developed after 10 days of treatment. At the same time, his digestive tract stenosis worsened, making Loperamide unusable. We administered octreotide 200μg continuous intravenous drip infusion. One day after octreotide administration, the number of diarrhea has decreased from 20 times to four times. Conclusions: Octreotide is one of the effective treatments for CPT-11-induced diarrhea. Palliat Care Res 2010; 5(2): 338-341