Abstract: High efficiency hydrate inhibitors are generally used in offshore deep water drilling to prevent the formation of hydrate which is able to plug pipelines and subsea blowout preventers (BOPs). In laboratory experiment, the decomposition of sI hydrate by glycerol triacetate and the synergy between glycerol triacetate and NaCl were studied at 4℃ and 20 MPa, using NPT ensemble molecular dynamics. The experimental results showed that the hydrogen bonds between glycerol triacetate and water destroyed the cage structure of the hydrate molecules. NaCl is able to reduce the activity of water, thereby destroying the equilibrium conditions under which the hydrate is stabilized. The decomposition of hydrate mainly takes place in the first 50 ps; the diffusion coefficient of the hydrate molecules under the co-action of glycerol triacetate is greater than the diffusion coefficient of the hydrate molecules under the action of glycerol triacetate alone. At 4℃ and 20 MPa, the reaction equilibrium pressure of 0.5% glycerol triacetate is 18.75 MPa, and that of 0.5% glycerol triacetate + 10% NaCl is 18.91 MPa, verifying the hydrate inhibitive capacity of glycerol triacetate and the synergy between glycerol triacetate and NaCl. The study findings can be used in developing new hydrate inhibitors for ultra-deep water drilling and in formulating hydrate inhibitors.