Objective To investigate the discriminant validity and relativity of three scales applied in fall risk estimation for senile patients.Methods The timed up and go test (TUGT),the Morse Fall Scale (MFS) and the Berg Balance Scale (BBS) were used by two trained testers to evaluate the fall risk of 161 senile in-patients.The patients were divided into a falling group and a no-fall group based on their history of falling in the previous one year.Student's t-test was applied to compare the discriminant validity of the TUGT,MFS and BBS.Spearman's correlation coefficient was calculated to analyze the correlation among the three scales.Results The scores of patients in the falling group on the three scales were significantly different from those of the no-falls group.The correlation coefficients among the three scales were in the range 0.680-0.888.Conclusion The TUGT,MFS and BBS all showed high sensitivity and good discrimination in fall risks estimation for senile patients.The results with the three scales were highly correlated.Because the emphasis of these three scales is different,a suitable scale should be selected in clinical practice according to the characteristics of the senile patient.