HI distribution in the region of radio source Cygnus X and supernova remnant G78.2+2.1 has been investigated from observations in 21 cm radio line using radio telescope RATAN-600. Two HI envelopes have been distinguished: the first one (diameter approximate 7 degree) surrounds the entire extended termal radio source Cygnus X, the other one (diameter approximate 2 degree) is located around the supernova remnant (figure 1). Both envelopes show an expansion with velocities higher than 10 km/c. To compare HI velocities with that of ionized gas we provided H_l observations with an interferometer Fabry-Perot at 125 cm telescope of the Crimea Laboratory of Sternberg Astronomical Institute.
Basing on CO data we also discussed the molecular gas distribution in the region around Cygnus X and found large cavity around all Cygnus X system. We determined physical parameters of the HI shells and speculated about their nature. The existance of the large HI shell and a cavity in molecular gas distribution around Cygnus X indicates this radio source most probably to represent a united structure and whole gas may be drived by stellar wind of Cyg OB2 stellar assotiation. The smaller HI shell around G78.2+2.1 may be created both by the supernova explosion or by the action of stellar wind of the precursor star.

Figure 1. Contours of HI details in the region of Cygnus X radio source. The boundaries of ring structures around super nova remnant G38.2+2.1 and whole source are marked by dashed lines.