  Sulfur chemistry in the formation process of low-mass stars and planets
remains poorly understood. The protoplanetary disks (PPDs) are the birthplace
of planets and its distinctive environment provides an intriguing platform for
investigating models of sulfur chemistry. We analyzed the ALMA observations of
CS 7-6 transitions in the HD 163296 disk and perform astrochemical modeling to
explore its sulfur chemistry. We simulated the distribution of
sulfur-containing molecules and compared it with observationally deduced
fractional column densities. We have found that the simulated column density of
CS is consistent with the observationally deduced fractional column densities,
while the simulated column density of C$_2$S is lower than the observationally
deduced upper limits on column densities. This results indicate that we have a
good understanding of the chemical properties of CS and C$_2$S in the disk. We
also investigated the influence of the C/O ratio on sulfur-containing molecules
and found that the column densities of SO, SO$_2$, and H$_2$S near the central
star are dependent on the C/O ratio. Additionally, we found that the
$N$[CS]/$N$[SO] ratio can serve as a promising indicator of the disk's C/O
ratio in the HD 163296. Overall, the disk of HD 163296 provides a favorable
environment for the detection of sulfur-containing molecules.
