The automotive chassis components are structural assemblies that support the engine, suspension, and steering components of vehicles. For the development of AHSS chassis components, the weld parts’durability of them is very important. In this paper, the effect of torch angle, push angle, weld voltage, weld speed and gas is precisely analyzed. Maintaining the same heat input level, the difference of fatigue life is investigated according to changing torch and push angle. The more torch and push angle are large, the more the fatigue life is long. In this study, Hot Spot Stress, HSS, is also measured precisely by using strain gages attached on the fatigue weld specimens. Toe angle is a main factor to control HSS of weld specimen. To enhance weld fatigue life of automotive components, it is necessary to make toe angle large.