本文在随机波浪底部剪应力的研究中引入了波浪谱的概念． 根据浅水波的特点， 将波浪谱作为输入谱，通过传递函数确定作为输出谱的随机波浪作用下的底部剪应力谱． 本研究中研制了一套底部剪应力测量仪． 对于层流边界层得到了底部剪应力谱的理论解， 并得到了实验的检验 This paper introduced the concept of wave spectrum in the study of shear stress at the bottom of random wave. According to the characteristics of the shallow water wave, the wave spectrum is taken as the input spectrum, and the bottom shear stress spectrum under the random wave which is the output spectrum is determined by the transfer function. In this study, a set of bottom shear stress gauge was developed. The theoretical solution of the bottom shear stress spectrum was obtained for the laminar boundary layer and was tested experimentally