  We present the result of three BeppoSAX observations of the X-ray binary
pulsar A0535+26 in its quiescent state. The source is quite well detected up to
200 keV (6 sigma detection in the stronger observation). No Iron line is
detected in the MECS data (3 sigma upper limit on its equivalent width of 150
eV). There is evidence of a soft excess below 2 keV. Pulsation is detected in
all energy bands up to 10 keV, with a pulsed fraction of ~ 0.5, not varying
with energy. There is a marginal detection (4 sigma) of a cyclotron resonance
feature (CRF) at 118 +/- 20 keV in the PDS spectrum. During the BeppoSAX
observations HDE 245770, the optical counterpart to A0535+26, was monitored
spectroscopically and photometrically. These observations show that the Halpha
and Hbeta lines previously observed in absorption returned in emission,
indicating that the Be disk formed again. The presence of pulsation and a CRF
is a clear indication that accretion onto the polar caps is occurring, and that
the propeller mechanism is leaking. The presence of a soft excess could be
explained either in terms of thermal emission (kT ~ 1.2 keV) from the neutron
star surface, as observed in other accreting X-ray pulsars, or in terms of an
overabundance of Mg in the circumstellar matter.
