In this work, we present the analysis of the binary microlensing event OGLE-2018-BLG-0022 that is detected toward the Galactic bulge field. The dense and continuous coverage with the high-quality photometry data from ground-based observations combined with the space-based {it Spitzer} observations of this long time-scale event enables us to uniquely determine the masses $M_1=0.40 pm 0.05~M_odot$ and $M_2=0.13pm 0.01~M_odot$ of the individual lens components. Because the lens-source relative parallax and the vector lens-source relative proper motion are unambiguously determined, we can likewise unambiguously predict the astrometric offset between the light centroid of the magnified images (as observed by the {it Gaia} satellite) and the true position of the source. This prediction can be tested when the individual-epoch {it Gaia} astrometric measurements are released.
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