Abstract: In order to understand the influence of the molecular structure of gas hydrate kinetics inhibitors on its inhibitory performance, the interactions between kinetics inhibitors with different structures and water molecules were analyzed. By utilizing a molecular simulation method, the interactions between water molecules with the cyclic structure-bearing kinetic inhibitors (PVP and PVCap), the chain structure-bearing kinetic inhibitor (PMC), and the novel kinetic inhibitor containing both cyclic structure and chain structure (YZ) were studied. The study found that the interactions between kinetics inhibitors and water molecules were closely related to the structures of kinetic inhibitors. First, the cyclic structure-bearing kinetic inhibitors could effectively reduce the diffusion coefficient of water molecules in the solution. Second, the chain structure-bearing kinetic inhibitor could form more hydrogen bonds with water molecules, and the kinetic inhibitor containing both cyclic structure and chain structure presented stronger inhibition. The study results further clarified the influencing mechanism of kinetic inhibitor molecular structure on its inhibition performance, which demonstrated itself to be effective for guiding the development of gas hydrate kinetic inhibitors.