Treating liver and spleen together plays an important role in the treatment for irritable bowel syndrome. Tongxie Yaofang is a representative decoction for treating abdominal pain and diarrhea due to liver and spleen disharmony. This paper reviewed the studies of Tongxie Yaofang’s pharmacological mechanisms in treating irritable bowel syndrome in the past five years. The pharmacological mechanisms include regulation of brain-gut interaction, reducing visceral sensory hypersensitivity, adjusting immune function, etc. Studies have shown that IBS has complex pathogenesis and the mechanisms of Tongxie Yaofang may act on multiple levels that interrelated.