  In this article, we take the $X(5568)$ to be the scalar diquark-antidiquark
type tetraquark state, study the hadronic coupling constant $g_{XB_s\pi}$ with
the three-point QCD sum rules by carrying out the operator product expansion up
to the vacuum condensates of dimension-6 and including both the connected and
disconnected Feynman diagrams, then calculate the partial decay width of the
strong decay $ X(5568) \to B_s^0 \pi^+$ and obtain the value
$\Gamma_X=\left(20.5\pm8.1\right)\,\rm{MeV}$, which is consistent with the
experimental data $\Gamma_X = \left(21.9 \pm 6.4
{}^{+5.0}_{-2.5}\right)\,\rm{MeV}$ from the D0 collaboration.
