  The bottom quark forward-backward asymmetry $A_{\rm{FB}}$ is a key observable
in electron-positron collisions at the $Z^{0}$ peak. In this paper, we employ
the Principle of Maximum Conformality (PMC) to fix the $\alpha_s$-running
behavior of the next-to-next-to-leading order QCD corrections to $A_{\rm{FB}}$.
The resulting PMC scale for this $A_{\rm{FB}}$ is an order of magnitude smaller
than the conventional choice $\mu_r=M_Z$. This scale has the physically
reasonable behavior and reflects the virtuality of its QCD dynamics, which is
independent to the choice of renormalization scale. Our analyses show that the
effective momentum flow for the bottom quark forward-backward asymmetry should
be $\mu_r\ll M_Z$ other than the conventionally suggested $\mu_r=M_Z$.
Moreover, the convergence of perturbative QCD series for $A_{\rm{FB}}$ is
greatly improved using the PMC. Our prediction for the bare bottom quark
forward-backward asymmetry is refined to be $A^{0,b}_{\rm FB}=0.1004\pm0.0016$,
which diminishes the well known tension between the experimental determination
for this (pseudo) observable and the respective Standard Model fit to
$2.1\sigma$.
