This paper reports the use of Bi2O3-modified carbon nanotubes paste electrode (Bi2O3-CNTPE) for trace lead (Pb), cadmium (Cd) and indium (In) determination by differential pulse anodic stripping voltammetry (DP-ASV). The stripping peak current (Ip) has a linear relationship with concentration in the ranie of Pb(II), In(III) and Cd(II) are 1.21 x 10-8 M to 4.83x 10-8 M, 5.22x 10-8 M to 12.l7x 10-8 M, 2.23x 10-8 M to 8.93x 10- M, respectively, with a deposition time of 60 s at deposition potential of -1.2 V, in 0.1 M acetate buffer (pH = 4.5) and 0.1 M KBr. The 3delta detection limit (n = 10) of Pb, in and Cd is 0.83 x 10-9 M, 6.47 x 10-9 M, 1.38 x 10-9 M, respectively. The electrode was applied to determination of Pb(II), In(III) and Cd(II) in water sample.