This study was conducted to evaluate the impact of splenectomy in living donor liver transplantation (LDLT) using left lobe grafts. The two hundred and fifty LDLT cases were divided into two groups: Group-S (n = 98, simultaneous splenectomy) and Group-NS (n = 152). Group-S had significantly increased recipient age (54.5 +/- 10.9 years vs. 46.3 +/- 17.0 years, p < 0.01), advanced liver diseases including Child class C (64.8% vs. 51.5%, p < 0.01), higher model for end-stage liver score (17.8 +/- 8.1 vs. 15.4 +/- 5.8, p < 0.01) and more patients with hospitalized status (67.4% vs. 48.0%, p < 0.01), and smaller graft volume/standard liver volume ratio (36.5 +/- 6.1% vs. 40.2 +/- 8.2%, p < 0.01). In Group-S, splenectomy decreased portal venous (PV) pressure decreased from 23.5 +/- 5.2 mmHg to 19.2 +/- 4.8 mmHg (p < 0.01). Group-S had significantly increased PV pressure at laparotomy (24.9 +/- 5.3 mmHg vs. 22.5 +/- 6.3 mmHg, p < 0.01) and decreased PV pressure at closure (16.4 +/- 3.5 mmHg vs. 18.0 +/- 4.7 mmHg, p < 0.01), compared with Group-NS. On the 14th day after LDLT, Group-S had lower total bilirubin (5.7 +/- 6.5 mg/dl vs. 8.7 +/- 8.9 mg/dl, p < 0.01) and smaller ascites output (0.4 +/- 0.7 L/day vs. 0.7 +/- 0.4 L/day, p = 0.01) than Group-NS. The cumulative 5-year graft survival rate was 86.8% in Group-S and 76.2% in Group-NS (p = 0.03). In conclusion, splenectomy had beneficial impacts on graft outcomes in left-lobe LDLT.