Abstarct: In recent years, increasing the competition in the automotive, aerospace and military industries has caused to industry centers led to the production of light equipment, with purpose of high strength to weight ratio especially in reduction of fuel consumption. In this case, producting of hollow parts with complex geometry from sheet and tube, by using flexible die forming have been focused by researchers. Rubber pad forming and hydroforming process are the most important methods by advantages of high flexibility in the production of complex parts, good surface quality and lower manufacturing costs, altered as alternative methods to the conventional forming proceses. In present research, numerical and experimental investigation of bulging 304 stainless steel seamed tube, using a polyurethane elastic pad has been studied. In the first, stress analysis of die sets under the rubber pad forming process conducted using 3D deformable parts and after some numerical trials on the material, geometry and die hardness; finally the die parts were designed. Then, to calculate the damage property and plastic instability factors, free bulging of the seamed tube simulated and forming limit diagram criterion was used as a damage initiation criterion. Results compared with experiments of others references. Also, with the aim of determining the effects of intrinsic and extrinsic parameters of rubber pad forming process by combining finite element and Taguchi design of experiments methods has been performed. In this section effect of seven factors such as, friction between tube and die, friction between tube and rubber, rubber height and hardness, die corner radius, length of deformation zone and tube axial feed has been studied. The response factors were average of bulging depth, maximum difference between depths, wrinkles numbers, thickness strain and standard deviation of strain was studied. At the end of numerical activity, 3D simulation of seamed tube bulging by using rubber pad forming under several lubrications has been performed. Results of numerical method showed that friction, especially between rubber and tube play the main rule in success of rubber pad forming process. In the experiment section, compression test of rubber was carried out according to ASTM D575-91 standard and compressive stress-strain curve and the Mooney-Rivlin constants was determined. Meshed tubes forming by using elastic pad with different lubricating systems have been conducted up to bursting onset in the seam weld observed and longitudinal, hoop and thickness strains were measured. Comparison of the strains obtained from the safe regions with the forming limit curve obtained from hydroforming process, showed increasing the formability in the rubber pad forming process. The experimental results showed that the intact parts without any wrinkles formed by using nylon lubricant between tube and rubber and drawing oil between tubes and die. Comparison between free bulging of tube using fluid and elastic pad showed that in rubber forming by increasing the hydrostatic pressure as more as unwanted axial feeding due to the friction between rubber and tube, distracting the strain path to the left side of FLD and formability increasing occur. It results to more depth of bulging. Finally, in order to investigate the efficiency and accuracy of rubber pad forming, in a case study, numerical simulation and experimental tests was used to forming of a tube cam type profile. This product formed successfully and the results were compared with hydroforming process.