Abstract: With the development of industry, the demands of human for energy are increasing, and gradually the exploration and development of oil and gas in the deep water became the main focus. There are many difficulties and chanlleges for exploration and development in deep water. The specific depth of the operation area makes the deep water drilling more difficult, and deep water drilling fluid operations maybe easily transformed to natural gas hydrates. Besides, it is difficult in returning for large-scale borehole cuttings. Furthermore, the rheology of low-temperature drilling fluid is hard to control, and leakage of drilling fluid easily occurs. Deep water drilling engineering is also a high-risk and high-investment operation. Therefore, the quality of drilling fluids is particularly important in deep water drilling projects.