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We have analyzed the kinematics of OB2 stars with proper motions andparallaxes selected by Xu et al. from the Gaia EDR3 catalog. The relativeparallax errors for all the stars in this sample do not exceed 10\%. Based on asample of 9750 stars, the group velocity components$(U,V,W)_\odot=(7.21,7.46,8.52)\pm(0.13,0.20,0.10)$~km/s were obtained and theparameters of the angular velocity of rotation of the Galaxy:  $\Omega_0 =29.712\pm0.062$~km/s/kpc,$\Omega^{'}_0=-4.014\pm0.018$~km/s/kpc$^{2}$ and  $\Omega^{''}_0=0.674\pm0.009$~km/s/kpc$^{3}$. The circular velocity ofrotation of the solar neighborhood around the center of the Galaxy is$V_0=240.7\pm3.0$~km/s for the assumed distance of the Sun to the galacticcenter $R_0=8.1\pm0.1$~kpc. It is shown that the influence of the systematiccorrection to the trigonometric parallaxes of the Gaia EDR3 catalog with thevalue $\Delta\pi=-0.040$~mas does not exceed the $\sim1\sigma$ level of theerrors of the sought-for kinematic parameters of the model. Based on the propermotions of OB stars, the following variances of the residual velocities werefound:$(\sigma_1,\sigma_2,\sigma_3)=(11.79,9.66,7.21)\pm(0.06,0.05,0.04)$~km/s. It isshown that the first axis of this ellipsoid slightly deviates from thedirection to the center of the Galaxy $L_1=12.4\pm0.1^\circ$, and the thirdaxis is oriented almost exactly to the north pole of the Galaxy,$B_3=87.7\pm0.1^\circ.$

Galaxy Rotation Parameters from OB2 Stars with Proper Motions and Parallaxes from the Gaia EDR3 Catalog