  The China Space Station Telescope (CSST) is a two-meter space telescope with
multiple back-end instruments. The Fine Guidance Sensor (FGS) is an essential
subsystem of the CSST Precision Image Stability System to ensure the required
absolute pointing accuracy and line-of-sight stabilization. In this study, we
construct the Main Guide Star Catalog for FGS. To accomplish this, we utilize
the information about the FGS and object information from the Gaia Data Release
3. We provide an FGS instrument magnitude and exclude variables, binaries, and
high proper motion stars from the catalog to ensure uniform FGS guidance
capabilities. Subsequently, we generate a HEALPix index, which provides a
hierarchical tessellation of the celestial sphere, and employ the Voronoi
algorithm to achieve a homogeneous distribution of stars across the catalog.
This distribution ensures adequate coverage and sampling of the sky. The
performance of the CSST guide star catalog was assessed by simulating the field
of view of the FGS according to the CSST mock survey strategy catalog. The
analysis of the results indicates that this catalog provides adequate coverage
and accuracy. The catalog's performance meets the FGS requirements, ensuring
the functioning of the FGS and its guidance capabilities.
