Abstract: Three dimensional finite element model of welding beam-column connection components,including angle steel,bolt,beam and column,is established by taking account of the effect of temperature on the thermo-physical properties and mechanical properties of metal,and the temperature and the residual stress distributions during heating and cooling process are accurately computed by using of ANSYS software.The results show that the welding region is dominated mainly by tensile stress and different components possess different residual stress value.The maximum and minimum residual stresses occur in the bolts,which are 220.8% and 11.45% of the designing strength value respectively and are in accord with 'Code of Steel Structure'.