Abstract: Plate butt welding tests at different vibratory welding parameters were designed to investigate the influence of welding heat input and vibratory acceleration on maximum welding temperature.A mathematic model of maximum temperature was founded based on the multivariant nonlinear regression analysis.The results show that the peak temperature increases with the increase of vibratory acceleration at the higher welding heat input.The peak temperature increases initially and then decreases with the increase of vibratory acceleration at medium and lower welding heat input.According to the test results of correlation,linear regression significance and regression coefficients significance,the proposed model is feasible.The relationship between the regression coefficient related to vibratory acceleration and the distance of measuring points to weld center line was studied.The results show that vibratory acceleration has a significant effect on the temperature of the molten pool center.