Abstract: This paper has studied the effect of ratio between wavelength and diameter of hole on the stress distribution around hole during passage of a triangular stress pulse by using dynamic finite element code. The computations for seven different ratios between wavelength and diameter of hole have carried out. Besides the complete curve of variations of dynamic stress concentration factors with the ratios the changes of whole stress field around hole were obtained, particularly, the variations of values and distribution regions of radial and tangential tension stresses around hole. In addition, the effect of the length of pulse front (rise from zero to peak) was considered and the comparisons of the stress distributions around hole during that the peaks of two stress pulses of different wavelengths pass a hole with the corresponding static cases have been made.