The frequency spectra of the wave profile are measured for wind waves generated by the air flow on water surface in a waterway, in which the depth of water is taken 15cm and 3cm respectively. Waves are sustained at stationary states. The analysis of the high frequency part of these spectra (the high frequency part means components which have the higher frequency than the frequency of the peak intensity of spectrum) has been made in connection with author's view of the characteristics of of the spectrum, which are revealed when the expression E(f)～f-n indicates n＞5 in the case of deep water.
　The results of analysis of experimental date show that, (ⅰ) the intensity of high frequency part of the spectrum changes progressively its value from windward to leeward in closely correlated forms with the value of n, and (ⅱ) the attenuation coefficient of the intensity of high frequency part concerned with the running distance of wave energy has similar values in both cases of wind waves under the direct wind action and of wind-generated waves in the calm condition, when the value of n becomes 7～10 in like manner.