The aim of this study was to evaluate the Mayo Adhesive Probability (MAP) score as a predictor of split renal function deterioration after robot-assisted partial nephrectomy (RAPN). A total of 30 patients who underwent RAPN were identified retrospectively. The parameters evaluated included patient characteristics, tumor diameter, MAP score, warm ischemic time (WIT), and renal function. Split renal function was evaluated using Tc-99m DTPA renal scintigraphy before and six months after surgery. Univariate and multivariate logistic regression analyses were performed. Nine patients (30.0%) showed more than 90% preservation of split renal function on the operated side. The MAP score (p=0.015), cT1b tumor (p=0.0002), and WIT (p=0.044) were associated with preservation of split renal function six months after surgery on univariate analysis. The MAP score was the strongest predictor of preservation of split renal function six months after surgery on multivariable analysis (p=0.007). On receiver-operating characteristic (ROC) curve analysis, the MAP score (cutoff value 3.0; p=0.01) was a significant predictor of split renal function six months after surgery. The MAP score was significantly associated with postoperative split renal function six months after RAPN on the operated kidney side. The MAP score is useful for predicting split renal function after RAPN.