  By taking into account the effect of toroidal magnetic field and its
correspond heating, we determine the thickness of advection-dominated accretion
flows. We consider an axisymetric, rotating, steady viscous-resistive,
magnetized accretion flow under an advection dominated stage. The dominant
mechanism of energy dissipation is assumed to be turbulence viscosity and
magnetic diffusivity. We adopt a self-similar assumption in the radial
direction to obtain the dynamical quantities, that is, radial, azimuthal, sound
and Alfv\' en velocities. Our results show the vertical component of magnetic
force acts in the opposite direction of gravity and compresses the disc, thus
compared with the non-magnetic case, in general the disc half-thikness,
$\Delta\theta$, significantly is reduced. On the other hand, two parameters,
appearing due to action of magnetic field and reaction of the flow, affect the
disc thickness. The first one, $\beta_0$, showing the magnetic field strength
at the equatorial plane, decreases $\Delta\theta$. The other one, $\eta_0$ is
the magnetic resistivity parameter and when it increases, $\Delta\theta$
increases, too.
