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The hydrate-based CO 2 sequestration provides an alternative solution for reducing CO 2 emissions. However, the hydrate film that forms preferentially at the CO 2 -water interface can severely restrict hydrate conversion rate. How to enhance CO 2 hydrate formation remains a crucial question. Here, we constructed static and shear flow contact models of liquid CO 2 and brine in a cubic cavity and investigated their hydrate growth behavior at different subcoolings from perspectives of morphology and kinetics. For static contact, nucleation usually occurs at the CO 2 -brine interface, and high subcooling increases the degree of hydrate film wrinkling and the CO 2 hydrate formation amount. The shear flow can delay the explosive growth of hydrates and tends to nucleate in bottom water; meanwhile, the continuous flow causes the overall extrusion deformation of hydrate film until the injection hole is blocked. Compared to static contact, this forced CO 2 -H 2 O contact caused by film deformation enhanced the CO 2 hydration amount by 2.68–3.62 times at the subcoolings of 6.94–3.25 K. Increasing the flow rate can further delay hydrate appearance and enhance hydrate growth. We also speculate on the hydration patterns of CO 2 in sediment pores under static and flowing conditions, and think that maintaining long-term flow can be an effective means to improve CO 2 hydrate storage and prevent blockage occurring in the pore throat. Our work provides new insights into the growth behavior of CO 2 hydrate for future CO 2 storage in submarine sediments. • The model of continuous shear flow contact of liquid CO 2 and seawater in marine environment is constructed. • The relationship between induction time and injection rate is revealed. • Subcooling and shear flow cause hydrate film deformation with morphological difference. • Shear flow can significantly enhance CO 2 hydration formation. [ABSTRACT FROM AUTHOR]