Purpose: The purpose of this study was to determine the correlations, if any, between SPPB (Short physical performance battery), FRT (Functional reach test), and TUG (Timed up and go test) in hospitalized frail people. Methods: Seventy frail elderly patients (male/female: 16/54) participated in this study. All subjects could walk with or without an assisting device and they had no mental problems. Subjects were scored on physical functioning using the SPPB, FRT, and TUG. The data were analyzed using Pearson Correlation Coefficients. Results: There was a statistically significant difference between (a) SPPB and (b) FRT (p<0.01) and TUG (p<0.01). SPPB and FRT scores showed a positive correlation (r = 0.38) and SPPB and TUG scores showed a negative correlation (r = -0.56). Conclusion: SPPB, FRT, TUG scores are correlated with each other. From these results, we conclude that the SPPB is a useful method for predicting walking, balance, and physical function in frail elderly people.