Portopulmonary hypertension (PPHTN) is a rare complication of liver cirrhosis. Patients with severe PPHTN are contraindicated for liver transplant because of the associated risk of intraoperative acute right heart failure during reperfusion phase or massive volume infusion. Therefore, it has been recommended that patients with moderate to severe PPHTN undergo medical treatment to lower the pulmonary artery pressure before undergoing transplant. Herein, we report 3 patients with severe PPHTN who underwent sildenafil monotherapy before living donor liver transplant. None of the patients experienced associated adverse effects during sildenafil treatment, and the pulmonary artery pressure was effectively reduced before transplant. The first patient was diagnosed during anesthesia prior to transplant, and the mean pulmonary artery pressure was reduced by 34% after treatment. The second and third patients were followed-up with echography, and the estimated pulmonary artery systolic pressure were reduced by 34% and 47%, respectively. Pretransplant right heart catheterization also confirmed the reduction of the mean pulmonary artery pressure. Intraoperative hemodynamic parameters were stable, and the 3 patients were discharged uneventfully. After transplant, sildenafil was discontinued, and all patients remained in a stable clinical and functional status during follow-up.