  HD 50138 is a southern star that presents the B[e] phenomenon, but its
evolutionary stage is still not well known. This object presents spectral
variability, which can be explained by outbursts or shell phases and
spectropolarimetric observations have shown the presence of a non-spherically
symmetric circumstellar environment that is responsible for the B[e]
phenomenon. Based on recent optical long baseline interferometric observations
from the VLTI/MIDI and VLTI/AMBER, and also from the Keck segment-tilting
experiment, we study the structure of the circumstellar environment of HD
50138, through a geometrical analytical modeling, also using the recent LITpro
software and considering a large space of parameters. We resolve and describe
its circumstellar geometry for the first time in detail. The presence of a
dusty circumstellar disk with an orientation onto the sky-plane of 71+-7
degrees, which is perpendicular to the polarimetric measurements from the
literature, was derived. We also derived that HD 50138 is seen under an
intermediate angle related to the line of sight, 56+-4 degrees. In addition,
the structure of the disk and the flux contributions of the gas and dust
components is discussed.

Solar and Stellar Astrophysics