  We probe the inner structure of the meson $D^*_{s0}(2317)$ through the decays
of $B_{(s)}$ to two charmed mesons within pQCD approach. Assuming
$D^*_{s0}(2317)$ as a scalar meson with $\bar cs$ structure, we find that the
predictions for the branching ratios of the decays $B^+\to
D^{*+}_{s0}(2317)\bar D^{(*)0}, B^0\to D^{*+}_{s0}(2317)D^{(*)-}$ can explain
data within errors. The branching ratios for the decays $B_s\to
D^{*+}_{s0}(2317)D_s^{(*)+}$ are estimated to reach up to $10^{-3}$ order,
which can be observed by the present LHCb and SuperKEKB experiments. In this
work, the decay constant of the meson $D^*_{s0}(2317)$ is an input parameter.
Unfortunately, its value has been studied by many references but with large
uncertainties. Our calculation shows that a smaller decay constant of the meson
$D^*_{s0}(2317)$ is supported by compared with the present data, say $55\sim70$
MeV. We also calculate the ratios $R_1=\frac{Br(B^+\to D^{*+}_{s0}(2317)\bar
D^0)}{Br(B^+\to D^{*+}_{s0}(2317)\bar D^{*0})})$ and $R_2=\frac{Br(B^0\to
D^{*+}_{s0}(2317)D^-)}{Br(B^0\to D^{*+}_{s0}(2317)D^{*-})}$, which are valuable
to determine the inner structure of $D^*_{s0}(2317)$ by compared with the
experimental results. Our predictions for the ratios $R_{1,2}$ are consistent
with the present data within errors.We expect that these two ratios can be well
measured by the future experiments through improving the measurement accuracy
for the decays $B^+\to D^{*+}_{s0}(2317)\bar D^{*0}$ and $B^0\to
D^{*+}_{s0}(2317)D^{*-}$.
