Notches greatly increase the stress concentration in mechanical elements. The high amount of stress concentration can often lead to failure of machine parts, which can be dangerous effect for many parts of machine. Moreover, notches in plates cannot be avoided in design of many parts and come in non-suitable places. This article presents an attempt to evaluate the effect of bi-axial state of stress on the stress concentration factor of flat plates with notches of different shapes such as semi circular, V-shaped and sharp-edge notches. In Addition, plates with two successive similar notches have been studied. The computation is carried out using JL-Analyzer finite element package under plane stress conditions and under the application of tensile normal stress that generated from normal load together with shear stress. The results show that the type of loading affects significantly the value of the stress concentration factor “kt” where its value by bi-axial state of stress is greater th