Mud plays an important role in foundation treatment, mud-water shield and other projects, and the thickener is the key to the quality of mud. The thickening agent used in traditional mud is mainly sodium carboxymethyl cellulose (CMC), which is difficult to degrade and easily pollutes the environment. To address the above problems, guar gum and xanthan gum were used to replace the traditional mud additives for green mud configuration. The optimal ratio of the mud and the permeability characteristics of its new mud skin were studied through proportioning experiments and improved filtration loss experiments. The results show that the optimal ratio of guar gum to xanthan gum is 1∶5, and the permeability coefficient of the mud skin can be effectively reduced by increasing the test pressure. The effect of CMC and the new additives on the mud modification is roughly the same, and the permeability coefficient of the mud skin obtained with the addition of 2.5 g of guar gum to the bentonite clay and 0.5 g of xanthan gum is three orders of magnitude smaller than that of the same quality fraction of the pure bentonite clay slurry. The modification effect of the new natural additives on the mud is better, and the addition of polymer materials will make the thickness of the mud skin formed smaller. The results of the test and theoretical analysis prove the feasibility of the new green mud in the application of pile foundation engineering, which can be widely used.