Abstract. We present one-dimensional decomposition of edge-on galactic profiles in the spirit of Kormendy (1977) [18]. The profile is decomposed by means of the Sersic (1968) [25] formula, used both for the bulge and disk components. This method is applied on 22 deep profiles and has reached in all cases good fitting of the data. The RMS of the Tully-Fisher (1977) [29] relation ``absolute magnitude - HI line width'' is 0.34 mag, i.e. the magnitudes of the edge-on spiral galaxies are good distance indicators. We show that the edge-on surface brightness of the large and massive disks have well prominent convex shape, while in cases of small ones the surface brightness along the edge decreases almost linearly, i.e. almost exponentially in the intensity scale. The same conclusion has been made previously out of the profiles of the nearby galaxies M 31, M 33, LMC and SMC (Georgiev, 2004) [9]. Generally, the Freeman's exponential law for the radial disk profiles, introduced by Freeman (1977) [17] rests usable as the first approximation in the cases of small disks.

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