Generally, water pipes are buried underground and exposed to environment that is vulnerable to corrosion. When corrosion occurs on the surface of the pipe, the fatigue life is remarkably reduced due to the area reduction and the notch effect. In this case, water leak can be occurred due to crack initiation at the corroded part, and this may cause sinkholes and lead to serious accident. Therefore, it is necessary to evaluate the fatigue life of a material assuming that a pit due to corrosion has occurred. In this study, the base metal and the weldment test specimens were collected from the water pipe, and the fatigue life was estimated assuming that the corrosion pit was generated in each specimens. As a results, it was confirmed that the fatigue life of the specimen having the pit was lower than that of the specimen having no pit.