OAO 1657 - 415 is an accreting pulsar in an eclipsing binary system .
We analyzed the INTEGRAL core program observations of this object and obtained the eclipse light curve in the soft gamma-ray band between 15 and 40 keV .
We note that the gamma rays from the pulsar allow to probe the density profile of the outer layers of the B supergiant companion .
We find that the density profile of the outer layer can be described by a power law with the index \alpha = 8.5 .
We also note that the fit hints toward smaller inclinations of the system within the allowed range 60 ^ { \circ } < i < 90 ^ { \circ } ( Chakrabarty et al . 1993 ) .