Solid complex Zn(Thr)SO4*H2O was prepared in a water-acetone system. Under linearly increasing temperature, the non-isothermal kinetics and the decomposition mechanism of Zn(Thr)SO4*H2O were studied by means of thermogravimetry and IR spectrometry. The thermal decomposition processes of the complex could be divided into three stages. The non-isothermal decomposition mechanism and the kinetics parameters of the ligand-lost process were obtained from an analysis to the TG-DTG curves at various heating rates of 5.0, 10.0, 15.0 and 20.0 K/min by two integral and three differential methods. The results show that the random nucleation and the subsequent growth mechanism (n=3/2) controlled the ligand-lost process, the corresponding activation energy E and pre-exponential constant A are 139.96 kJ/mol and 1011.32 s-1, respectively. The empirical kinetics model equation was constructed.