Abstarct: The springs are one of the most important and vital parts of the machine that according to their type of applications, may be under severe static or dynamic loading conditions. Therefore, the design and manufacturing process of them is very critical. Residual stress induced in the manufacturing process of the spring, plays an important role in its performance. Understanding of the effects of manufacturing stages on the residual stress is an essential step towards achieving a satisfying improvement in the design and manufacturing process. Coiling, shot peening and presetting are three main stages of manufacturing process of coil spring. In coiling, straight wire is deformed into a spiral coil. Then it subjected to shot peening which involves impacts of high velocity shots on the material. In the presetting stage, the spring is compressed to solid height and then released. In this study, 3D simulation of above processes were performed to investigate the induced residual stress using the finite element software ABAQUS. Case study is a kind of automotive suspension helical spring produced in Iran Fanarlool Company at ambient temperature. The coiling and shot peening processes simulation were performed by explicit solver and the preset process was simulated using standard solver. In shot peening simulation, a MATLAB code has been generated to produce a random distribution of shots. Two types of rigid and elastic-plastic shots were considered. In the case of elastic-plastic shots, oblique impact and vertical impact with contact between shots were included in the model. In preset simulation, residual stresses induced in shot peening is transferred to one turn of coil spring in the preset model. The dimensions of the spring resulted from analysis were very close to the real case. Distributions of strain, stress at moment of coiling and residual stress after coiling were studied. At the moment of coiling, maximum value of stress was seen in the inner and outer diameters of spring. Residual stress distribution after coiling shows that the stress value in maximal at the center of wire. The feeding force, effects of friction coefficient and feed rate was obtained. By increasing in friction coefficient, maximum value of equivalent plastic strain and stress increased but these effects are not considerable. With increase in the number of impacts, the residual stress increases up to the saturation point. The best correlation to the experimental result was obtained for the elastic-plastic shots contacting each other. Reduction in length of the spring obtained from simulation was close to the real value. Distribution of stress at solid height and residual stress after preset was obtained. In order to verify the numerical analysis results, comparisons were made with the results available in the literature.