A dark purple tongue with teeth marks suggests weakness of spleen qi (weak spleen qi) and blood stasis. The dark purple color of the tongue is mostly due to poor blood circulation and stagnation, and the teeth marks on the tongue are due to the deficiency of spleen qi and the malfunctioning of fluid circulation, and the tongue is usually fat and large, thus forming teeth marks. Treatment should be based on the principle of strengthening the spleen and qi, activating blood circulation and removing blood stasis, which can be combined with the symptoms, tongue and pulse to identify and select prescriptions. If the deficiency of spleen qi is the main cause, Sijunzi Tang can be used with medicines that promote qi and blood circulation, such as danshen and peach kernel. If blood stagnation is the main cause, Tao Hong Si Wu Tang and Blood Matter Chasing Blood Stasis Tang can be used to strengthen the spleen and benefit the qi, such as Rhizoma Atractylodis Macrocephalae and Radix et Rhizoma Ginseng. Specific need to be under the guidance of the doctor to identify and treat, do not take medication without authorization.