Small-for-size syndrome (SFSS), which is characterized by synthetic dysfunction and prolonged cholestasis, is a major cause of worse short-term prognoses after living donor adult liver transplantation (LDALT). However, the risks of SFSS remain unclear. The aim of this study was to clarify the risks of SFSS, which were analysed in 172 patients who underwent LDALT for chronic liver disease. Graft types included left lobe with caudate lobe graft (n = 110) and right lobe graft (n = 62). Thirty-four cases (24 with left lobe grafts and 10 with right lobe grafts) were determined as SFSS. SFSS developed even if the actual graft-to-recipient standard liver volume ratio was >40%. Logistic regression analysis revealed three independent factors associated with SFSS development in left and right lobe grafts: donor age, actual graft-to-recipient native liver volume ratio, and Child's score. Donor age and actual graft-to-recipient native liver volume ratio may become predictive factors for SFSS development in left and right lobe grafts in patients undergoing LDALT.