In this research first the analysis of integrally stiffened panel has been made using FE code ANSYS. Hoop, Axial and Radial stress are calculated for the stiffened panel subjected to internal pressure. Secondly, crack growth characteristics of the integrally stiffened panel and conventional stiffened panel based on fracture mechanics and FE analysis are investigated. A fourteen-stringer stiffened panel is analyzed for a central skin crack propagating towards the adjacent stringers. Stress intensity factors and fatigue crack propagation rates of both types of the stiffened panels are then...