Abstract: Aiming at the non-uniform wall thickness defect of the initial thin-walled tube, which causes the difference of wall thickness distribution in hydraulic bulging, two kinds of wall thickness deviation models, eccentricity model and ellipse model, are proposed according to the actual tube deviation. The initial wall thickness deviation rates of the two models are the same. Through finite element software analysis, the wall thickness distribution along the circumference and the maximum and minimum bulging height of the two models are obtained when the hydraulic pressure reaches 35 MPa. In the initial tube model, the deviation of invisible shape is only the deviation of wall thickness. As the bulging proceeds, the deviation of shape increases gradually, and the deviation of wall thickness also increases gradually. The initial wall thickness distribution of the two models is different. After bulging, the shape deviation and wall thickness deviation of the elliptic model are smaller than that of the eccentric model.