When ultrasound propagates to a crack, transmitted and reflected waves are generated. These waves have useful information for the detection of the crack lying in a structure. In this paper, using finite element analysis, displacements round a inclined crack were obtained for 4 different inclination angles. Fourier transformation is applied to the results to research the frequency characteristics depending on the various locations around the crack. 2-dimensional plane stress model is considered, and finite element software ABAQUS/Explicit is used.