  Using the high resolution spectral observations obtained with the Nasmyth
Echelle Spectrograph NES of the 6m telescope we analysed the optical spectrum
of the hydrogen-deficient binary star KSPer. The atmospheric parameters derived
are: effective temperature Teff=9500+/-300 K, surface gravity log g=2.0+/-0.5,
and microturbulent velocity Vt=9.5+/-0.5km/s. The hydrogen deficiency is
H/He=3x10^{-5}, iron abundance is reduced by 0.8dex; nitrogen abundance is very
high [N/Fe]=1.4, but carbon and oxygen abundances are low. The star luminosity
is log L/Lo=3.3. A complex absorption and emission structure of the NaI D
doublet was revealed. We suggest that the emission component forms in the
circumbinary gaseous envelope.
