Abstract: Using the finite element method, a mathematical model of temperature field for weld-repaired zone of white cast iron is constructed, and temperature field and heat cycle are analyzed. It is shown that the cooling rate is fast at the beginning of cool-down(about 400℃/s),the temperature distribution of welded joint is non-uniform, and the maximum temperature gradient occurs in the area near weld fusion line, which may cause crack. In addition,the excellent agreement between the calculated and measured values is shown.