The azimuthal dependence of Auger electron spectra for Si single crystal and amorphous surfaces, Si(LVV) and Si(KLL), observed with a cylindrical mirror analyzer (CMA) were studied in relation to their low-energy electron diffraction (LEED) patterns. For the Si(111)7 x 7 surface, the peak heights of the Si(LVV) Auger electron spectra were observed to have a variation of 15% (maxima to minima) with an azimuth-angle period of 60-degrees, whereas those for the Si(111) and amorphous Si surfaces, displaying diffuse LEED patterns, showed a spectral deviation within 1.0% standard deviation for the azimuth. It was found that the sharp and diffuse LEED patterns had a close relation with the observed Auger spectra obtained by a conventional CMA having a considerably large detection area of Auger electrons.