  Results of simultaneous {\it INTEGRAL} and optical observations of galactic
microquasar SS433 in May 2003 are presented. The analysis of the X-ray and
optical eclipse duration and hard X-ray spectra obtained by {\it INTEGRAL}
together with optical spectroscopy obtained on the 6-m telescope allows us to
construct a model of SS433 as a massive X-ray binary. X-ray eclipse in hard
X-rays has a depth of $\sim 80%$ and extended wings. The optical spectroscopy
allows us to identify the optical companion as a A5-A7 supergiant and to
measure its radial velocity semi-amplitude $K_v=132$ km/s. A strong heating
effect in the optical star atmosphere is discovered spectroscopically. The
observed broadband X-ray spectrum 2-100 keV can be described by emission from
optically thin thermal plasma with $kT\sim 15-20 keV$
