依据Ｄｏｕｇａｌｓ算子，阐述了一种改进的宽角光束传播法（ＷＢＰＭ），此方法和传统的宽角光束传播法相比，在几乎不增加计算时间和计算机资源的情况下，把原数值计算时横向截断误差从ｏ（Δｘ）２减小到ｏ（Δｘ）４。该方法在宽角光束传播计算中，更显示出其优越性。 According to the Dougals operator, an improved wide-angle beam propagation method (WBPM) is presented. Compared with the traditional wide-angle beam propagation method, this method does not increase the computational time and computer resources, The lateral truncation error decreases from o (Δx) 2 to o (Δx) 4. The method also shows its superiority in wide-angle beam propagation.