Abstract： To introduce Prof. RU Qingjing's clinical experience in treating depressive psychosis and mania from the liver based on syndrome differentiation. According to Prof. RU，depressive psychosis and mania stems from the inhibition of emotion. The pathogenic factors of the disease are nothing but phlegm pathogen， stagnation and congealing of qi and blood， and abnormal ascending and descending of the qi movement，eventually resulting in yin-yang disharmony. And it tends to occur in spring and in adolescence. All of these syndromes come from the disorderly qi flow of the liver. As a result， it is better to treat the disease from the liver based on syndrome differentiation. It can be treated by soothing the liver，clearing the liver heat，calming the liver，nourishing the liver，fortifying the spleen and dissolving phlegm，moving qi and invigorating blood，opening the orifices and awakening the spirit，so as to soften and free the liver qi. Only when yin is calm and yang is sound can depressive psychosis and mania be treated.