Gastric ''inflammation-cancer'' transformation stars from inflammation and ends as gastric cancer （GC）， and the pathogenesis is still unclear. In China， GC features high morbidity and mortality and poor prognosis， influencing the quality of life and physical and mental health of patients. Therefore， it is of great significance to construct the prevention and treatment system for GC. Chronic atrophic gastritis （CAG） plays a key role in the occurrence， development， and outcome of gastric ''inflammation-cancer'' transformation. Modern therapies for CAG generally aim at eliminating causes and alleviating clinical symptoms， which show satisfactory short-term efficacy， but the reverse and recurrence are common. Based on the holistic view， syndrome differentiation-based treatment， and the ''inflammation-cancer'' transformation in modern medicine， traditional Chinese medicine emphasizes both prevention and treatment， with individualized therapies for CAG and GC to control the transformation. According to the pathogenesis of CAG-asthenia in origin and sthenia in superficiality and deficiency-excess in complexity， this study proposed the theory of spleen deficiency and pathogen stagnation in CAG， and believed spleen deficiency， pathogen， and stagnation are respectively the root cause of， the main factor of， and the key to ''inflammation-cancer'' transformation， respectively. Spleen deficiency and pathogen stagnation are closely related to the process of the transformation. For the treatment， the spleen-invigorating and pathogen-eliminating method should be used for invigorating the spleen to consolidate original Qi， improve the blood supply in stomach， and regulate immunity， and eliminating the pathogen to relieve stagnation， reduce the occurrence of non-controllable inflammation， and improve inflammatory micro-environment. As a result， the gastric inflammation is controlled at the early stage and the gastric ''inflammation-cancer'' transformation is blocked. The gastric mucosal lesions are blocked， delayed， or even reversed. This study provides a new idea in clinical diagnosis and treatment of CAG and in the prevention of GC.