The life prediction information is useful for improving the component design methodology at the early developing stage. Many thick cylinders are subjected to complex cyclic loading spectrum ranging from small vibration to large load induction. This paper presents modeling of fatigue crack growth behavior in thick wall cylinder for outer surface cracked pipe subjected to internal pressure. There are many factors affecting fatigue crack growth such as; crack length, orientation of crack, thickens of the cylinder and the load ratio. Fatigue crack growth as consequence of service loads depends on many different contributing factors. With the help of a simulation fatigue crack growth in three-dimensional structures can either be predicted or explain for already existing failures. The simulation results showed that, more studies on the thick wall cylinder structure need to be performed in order to obtain more accurate fatigue life.