  We report on the results of a broad band (0.1-100 keV) spectral analysis of
the bursting atoll source MXB 1728-34 observed by the BeppoSAX satellite. Three
bursts were present during this observation. The spectrum during the bursts can
be fitted by a blackbody with a temperature of 2 keV. From the bursts we also
estimate a distance to the source of 5.1 kpc. MXB 1728-34 was in a rather soft
state during the BeppoSAX observation. The persistent spectrum is well fitted
by a continuum consisting of a soft blackbody emission and a comptonized
spectrum. We interpreted the soft component as the emission from the accretion
disk. Taking into account a spectral hardening factor of 1.7, we estimated that
the inner disk radius is $R_{\rm in} \sqrt{\cos i} \sim 20$ km, where i is the
inclination angle. The comptonized component could originate in a spherical
corona, with temperature of 10 keV and optical depth of 5, surrounding the
neutron star. A broad gaussian emission line at 6.7 keV is observed in the
spectrum, probably emitted in the ionized corona or in the inner part of the
disk. Another emission line is present at 1.66 keV.
