The hydrate-based CO2 storage in seafloor sediments offers the potential advantages such as large storage potential, minimal ecological impact, and low leakage risk, making it a promising solution for large scale application to achieve China's “dual carbon” goals. At present, the key to the industrial application of this technology is to enhance the conversion rate of CO2 hydrates and achieve highdensity CO2 solidstate storage. In this study, we explored the kinetic behavior of hydrate formation in CO2 emulsion systems with different CO2/H2O volume ratios, aiming to enhance the contact between CO2 and water, and compared it with the hydrate formation in traditional liquid CO2-seawater system. The results show that due to the highly dispersed nature of emulsions, the formation quantity, conversion rate and storage density of CO2 hydrates are higher than those in non-emulsion systems under the same conditions. Notably, at a water content of 50 vol%, the hydrate formation quantity tripled compared to nonemulsion systems. The conversion rate of CO2 increased with higher emulsion water content, facilitating more CO2 being stored in solid hydrate form, but the injection cost and CO2 hydrate storage density should be considered comprehensively. The CO2 hydrate formation rate increased with decreasing water content of emulsion in the early stage of formation, while it was relatively higher between 40 vol%~60 vol% in the middle and late stages. Ultimately, CO2 was sequestered in sediments in both liquid and hydrate phases. The total sequestration density of CO2 decreased with increasing emulsion water content, and there was an optimal emulsion water content for maximizing the sequestration density in the hydrates, achieving 59.91 kg/m3 and a hydrate saturation of 44.3% at a water content of 50 vol%. This study provides data support, insights, and new perspectives for hydratebased CO2 storage in submarine sediments.