The structural models of Si-doped glow discharge polymer (Si-GDP) were established using reactive force field molecular dynamics simulation (ReaxFF MD), and the effects of silicon content, hydrogen content, and density on its hybrid carbon bonding and mechanical properties were investigated. The results show that with the silicon content increasing, the molecules tend to form a silicon-containing macromolecule, and the types and number of small molecules decrease, the silicon content improves the mechanical properties by promoting the binding of carbon and silicon atoms and inhibiting the formation of end-group sp³CH₃. Besides, species such as ·C₂H₃, ·C₃H₅ and ·Si(CH3)₃ were found during the formation of Si-GDP, which were in good agreement with the thin film deposition experiment of glow discharge polymer. The hydrogen content is measured as the atomic ratio of hydrogen to carbon and silicon, as the ratio grows, the number of model molecules did not change significantly, the ratio of sp³C and sp³CH₃ increased, and the hydrogen content decreased the mechanical properties mainly by promoting the formation of sp³CH₃. With the density increasing, the number of molecular species in the model did not change much, and the proportion of sp²C in the model was significantly increased, while the proportion of sp³C was slightly increased, the mechanical properties of Si-doped hydrogenated amorphous carbon were mainly improved by increasing the proportion of sp²C. This study provides an example for constructing Si-GDP by ReaxFF MD, and may provide a new method and reference for evaluating the structure and mechanical properties of Si-GDP.