A fuel injector is an automotive part that supplies fuel into the cylinders of an internal combustion engine. An injector, in general, consists of various parts such as control valve bodies, pistons, needles, nozzle bodies, and bodies inside of which have fuel passage where highly pressurized fuel passes through. The pressurized fuel inside the fuel passage causes stresses and deformations of the bodies and parts of the injector, which may result in the failure or malfunction of the injector. In this paper, the stress distribution and deformation of a 2,000bar diesel fuel injector bodies are analyzed using finite element method.