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We will present a study on the mechanism of multiphoton dissociation of the $SO2$ molecule through the $H~$ Rydberg state. For this study, a homemade Wiley-McLaren linear time-of-flight (TOF) spectrometer was constructed to characterize the fragments produced during irradiation of $SO2$ with a laser beam in the $222-234$ nm region. Both $SO+$ and $S+$ fragment ions were detected but no parent $SO2+$ appeared. The mass resolved excitation spectra (MRES) of both $SO+$ and $S+$ display the $SO2C~B2\leftarrow X1A1$ vibrational progressions. The first photon in the studied region pumps $SO2$ to the $C~1B2$ electronic state. The second photon further excites the molecule to the $H~$ Rydberg state, where it dissociates into $SO+O$ and $S+O2$ fragments. The third photon then ionizes the SO fragment. From the power dependence of the ion intensity and a kinetic model we developed, we conclude that $S+$ is produced by a one-photon dissociation, $SO++h\nu \to S++O$. The internal energy distributions of the fragmentation products from dissociation of $SO2$ via the $H~$ Rydberg state were also obtained using an ion-imaging spectrometer. The following five dissociation channels are observed: $SO(B3\Sigma -)+O(3P2),SO(A3\Pi )+O(3P2)$, $S(1D)+O2(b1\Sigma g),S(1D)+O2(a1\Delta g)$, and $S(1D)+O2(X3\Sigma -)$.