The main cause of water-slick tongue is weakness of the spleen and stomach. Water-slick tongue is a condition in which there is excessive moisture on the tongue, even to the point of drooling when the tongue is stretched out. Weakness of the spleen and stomach includes types of spleen qi deficiency, spleen yang deficiency, stomach qi deficiency and stomach yin deficiency. When the patient’s spleen and stomach are weak, the yang function of the spleen will diminish and the function of transporting and transforming water and liquid will be unfavorable, resulting in the production of dampness and the malfunctioning of water metabolism, which will result in the water-slippery tongue. Water-slippery tongue means that the patient’s tongue surface has too much water, and there is the phenomenon of salivation when stretching out the tongue, and there is a wet and slippery feeling when touching the tongue surface. Slippery tongue can be treated with medicines such as Sen Ling Bai Zhu San, Xiang Sha Nang Yi Pill or Hu Zi Li Zhong Pill by traditional Chinese medicine practitioners after diagnosis. It is recommended that patients with slippery tongue should go to the hospital in time for examination to clarify the cause of the disease and be treated under the guidance of TCM practitioners.