Abstract: Beam like structures have wide application in engineering field. Earliest detection of damage is to avoid catastrophic failure in the structures. To predict the failure, changes in the dynamic responses are required to be analysed by using vibration analysis. Beam like structures have different type of loadings that may cause cracks in the beam. To ensure durable, safety and flawless performance during the lifetime of the beam like structures, it is mandatory to take care of cracks, inherent flaw and air voids in the structure. In case, if there is a pre-existing crack in the structure, mass and stiffness of the structure gets altered there by mode shape and natural frequency of the structure gets changed. In this work, vibration analysis of both un-cracked and cracked cantilever beam were done by commercially available Finite Element Analysis (FEA) software ANSYS. Natural frequency of the beam was obtained from vibration analysis. Beam having single edged notch at various locations were analysed and the results were compared with un-cracked beam. From the results, it is inferred that the fundamental frequency of the cracked beam reduces when the crack location moves from free end to fixed end and it is due to the stiffness reduction of the beam.