Corrosion fatigue tests were carried out in synthetic seawater, in order to clarify the temperature effect on the corrosion fatigue strength of coated ship steel. To simulate the shipbuilding construction process, KA 32 TMCP steel in 10 mm thickness was sprinkled with water in outdoor twice a day for 20 days. After the exposure, the surface preparation was conducted, and the tar epoxy resin was painted with 50, 100, 200, and 300 μm in thickness. These specimens were subjected to cyclic axial stress at 0.17 Hz in 25, 40 and 60°C synthetic seawater. For the comparison, corrosion fatigue tests of uncoated specimens were also carried out. In the low cycle region, the corrosion fatigue strength of the coated specimen was almost equivalent to that of uncoated. On the contrary, it was improved in the high cycle region. The temperature effect of the corrosion fatigue strength was assessed by introducing corrosion factor K _c , which implies the reduction rate of the corrosion fatigue strength against that at 25°C. The corrosion factor K, indicated 1.031.13 at 4060°C. In addition the maximum depth of the corrosion pits was found to be 3040 μm after 20-day exposure. In the long-life corrosion fatigue, cracks were initiated from such corrosion pits under the coating film before it was destroyed. Finally, effect of corrosion pits on the fatigue crack initiation behavior was considered under the conditions of surface preparation of specimens.