Abstract： A modified arctangentbased tracking differentiator (MATD) was designed to improve the performance of arctangentbased tracking differentiator with the difficulty of parameter adjustment and poor ability of noise restraint. First, the tracking function of MATD was constructed by introducing the nonlinear function and reducing design parameters, and its global uniformly asymptotical stability was proved. Then, the improvement mechanism of MATD was shown based on the convergence analysis of the tracking function of MATD. Finally, the parameter adjustment rule of MATD was obtained via analyzing the effects parameters on frequency domain characteristics. Simulation results demonstrate that MATD has the advantages of fast response, high precision and strong ability of noise restraint.