Manganese dioxide nanotubes possessing oxidase-like catalytic properties was synthesized by simple hydrothermal method.Influences of solution pH，temperature and catalyst dose on the catalytic performance of the nanotubes on the oxidation of 3，3'，5，5'-tetramethylbenzidine(TMB) were evaluated by measuring the UV-visible absorbance of the oxidation product of TMB.The optimum reaction conditions were as follows:concentration of manganese dioxide was 0.015 mg/mL，the reaction was conducted in pH 4.0 acetic acid-sodium acetate buffer solution at room temperature for 10 min. The influences of common metal ions on the enzyme-like catalytic performance of the manganese dioxide nanotubes were also investigated. The results indicated that lead(Ⅱ)ions revealed the most remarkable inhibition effect on the catalytic activity of manganese dioxide nanotubes. Based on this inhibition effect，a novel，highly sensitive and rapid colorimetric method for lead ions was developed.The calibration curve was linear over lead concentration in the range of 1.0×10-7-1.0×10-3 mol/L,and the detection limit was 3.0×10-8 mol/L.