Abstract: Based on the Huygens-Fresnel diffraction integral,the diffraction of laser beams with amplitude modulations passing serrated apertures is studied and compared with hard-edged circular apertures numerically.Furthermore,the effect of aperture parameters on the diffraction characteristics of laser beams with amplitude modulations is also analyzed.It is shown that,while maintaining a relatively large fill factor,the use of serrated apertures can suppress the diffraction modulations of axial intensity and reduce the nonuniformity of transversal intensity distributions.