  We suggest an approach to detect the conformation of single molecule by using
the photon counting statistics. The generalized Smoluchoswki equation is
employed to describe the dynamical process of conformational change of single
molecule. The resonant trajectories of the emission photon numbers $<N >$ and
the Mandel's $Q$ parameter, in the space of conformational coordinates
$\bm{\mathcal{X}}$ and frequency $\omega_L$ of external field
($\bm{\mathcal{X}}-\omega_L$ space), can be used to rebuild the conformation of
the single molecule. As an example, we consider Thioflavin T molecule. It
demonstrates that the results of conformations extracted by employing the
photon counting statistics is excellent agreement with the results of {\it ab
initio} computation.
