The evidence for defining a safe minimal remnant volume after living donor hepatectomy is insufficient. The aim of this study was to evaluate the outcomes of living donors with a remnant/total volume ratio (RTVR) < 30% after right hepatectomy according to the following selection criteria: the preservation of the middle hepatic vein (MHV), an age < 50 years, and no or mild fatty changes in healthy adults. All living donors who underwent right hepatectomy preserving the MHV at our institution between January 2005 and September 2011 were divided into 2 groups: group A with an RTVR < 30% and group B with an RTVR ≥ 30%. Perioperative data, complications by the Clavien classification, and outcomes with at least 15.1 months' follow-up were compared. Twenty-eight donors were enrolled in group A, and 260 were enrolled in group B. The estimated liver volume was strongly correlated with the actual graft weight (R2 = 0.608, P < 0.001). The calculated donation liver volume and the RTVR were significantly different between the 2 groups (P = 0.03 and P < 0.001, respectively). The peak postoperative aspartate aminotransferase levels, alanine aminotransferase levels, and international normalized ratios did not differ between the 2 groups. The peak total bilirubin level was higher for group A versus group B (P = 0.04). The hospital stay was longer for group A versus group B (P < 0.001). All donors recovered completely, and there were no significant differences in overall complications between the 2 groups. In conclusion, right hepatectomy preserving the MHV with an RTVR < 30% can be safely indicated for carefully selected living donors less than 50 years old with no or mild fatty changes. Liver Transpl 19:872-878, 2013. © 2013 AASLD.