The purpose of this study was to investigate the effect of body composition on IADL (Instrumental Activities of Daily Living) of the elderly. This study consisted of male elder(n=50) and female elder(n=60). The average age of elder male and female was 73.79, 70.42 years. The data were analyzed with correlation test and regression test using SPSSWIN ver 10.1 and MINITAB program. Body composition was measured using InBody 3.0(seoul, korea) of Segmental Multifrequncy Bioelectical Impedance Analyzer technique. IADL was measured with Philadelphia Geriatric Center IADL. The result of this study were the following : A correlation of body composition between IADL. 1. Body composition of the elderly had effect on IADL. 1)The free fat mass(kg) and total body water(1) in Body composition of male elder had positive effect on IADL. 2)The WHR(waist-to-hip ratio %) in Body composition of male elder had negative effect on IADL.