  Using TESS photometry and Rozhen spectra of the Be/gamma-ray binaries MWC 148
and MWC 656, we estimate the projected rotational velocity ($ {v} \sin i$), the
rotational period (P$_{\rm rot}$), radius (R$_{\rm 1}$), and inclination ($i$)
of the mass donor. For MWC 148 we derive P$_{\rm rot} = 1.10 \pm 0.03$~d,
R$_{\rm 1}= 9.2 \pm 0.5$~R$_\odot$, $i = 40^\circ \pm 2^\circ$, and $ {v} \sin
i =272 \pm 5$~km~s$^{-1}$. For MWC 656 we obtain P$_{\rm rot} = 1.12 \pm
0.03$~d, R$_{\rm 1}= 8.8 \pm 0.5$~R$_\odot$, $i = 52^\circ \pm 3^\circ$, and $
{v} \sin i =313 \pm 3$~km~s$^{-1}$. For MWC 656 we also find that the rotation
of the mass donor is coplanar with the orbital plane.
