Structural health monitoring (SHM) is the process of monitoring the performance and evaluating the state of health of structures based on measurements from on-structure sensing systems. This technique helps to detect the damages at the earlier stage before failure occurs. The occurrence of damage in a structure produces changes in its global dynamic characteristics such as its natural frequencies, mode shapes, modal damping, modal participation factors, impulse response and frequency response functions. Various methods are available to detect the damages based on the dynamic characteristics of the structures as damage alters the dynamic behaviour of the structure. Frequency Contour method is used in this paper, which is one of the less time consuming method, in which the damage location and size can be detected accurately. In a steel beam of size 20 mm x 20 mm and of length 300 mm, Numerical study is undergone to validate the Frequency Contour method. The free vibration analysis is done in the beam in undamaged state and the first three natural frequencies is obtained using ABAQUS, FEA Software. The same is done in damaged beams. In damaged beams cracks were created at various locations along the length of the beam by varying the depths to 5 mm, 10 mm, 12 mm and 15 mm. The ratio of damaged to undamaged natural frequencies gave the Normalized natural frequencies. The intersection of the contours of Normalized natural frequencies for the first three modes plotted gives the crack location and depth. In order to plot the contours of Normalized natural frequencies code is written in MATLAB. The prediction of damage by using Frequency contour method gave good results.