Abstract: The effect of the perpenticular intersection weld between the two cylindrical shells is analyzed by the numerical method. The longitudinal shrinkage model is established to analyze the distortion of the perpendicular intersection weld. The result shows that the partial decending along the circumference of the flange plane is caursed by the perpendicular intersection weld between the two cylindrical shells, and the inclination along the width of the flange is not obvious. The calculated results coincide well with the experimental ones. It is proved that the longitudinal shrinkage model for analyzing the distortion of the perpendicular intersection weld is reasonable.