Abstract：Objective：To analyze the medication patterns of traditional Chinese medicine （TCM） in the treatment of chronic atrophic gastritis （CAG） based on a latent structure model combined with association rules，thus providing a theoretical basis for clinical CAG treatment. Methods： A systematic search was conducted in China National Knowledge Infrastructure（ CNKI），China Biology Medicine disc（ CBM），VIP Information，and Wanfang Database for effective medical cases of CAG since the establishment of the databases up to March 1， 2025. After screening the literature，a database was established using Microsoft Excel，and latent structure model and association rules analyses were performed using Lantern 5.0 and RStudio software. Results： A total of 134 articles were included， yielding 12 TCM syndrome types. The main TCM syndrome types were stomach collateral blood stasis syndrome （2 486 cases， 27.14%） and spleen deficiency syndrome（ 1 943 cases，17.14%）. The analysis involved 190 Chinese herbal medicines， and the top five with the highest frequency were Glycyrrhizae Radix et Rhizoma，Atractylodis Macrocephalae Rhizoma， Poria， Codonopsis Radix， and Paeoniae Radix Alba. Herb properties were predominantly warm； herb flavors were mainly sweet， bitter， and pungent. The primary meridian tropisms were the spleen and liver meridians. In terms of effect categories， herbs were mostly categorized as deficiency-tonifying， blood-activating and stasis-resolving， and heat-clearing. Association rules analysis identified 20 strongly associated core herb pairs， with the highest support being Atractylodis Macrocephalae Rhizoma-Glycyrrhizae Radix et Rhizoma. Latent structure model analysis yielded six latent variables，four comprehensive clustering models，and nine core prescriptions. Conclusion：The nature of CAG is characterized by deficiency in origin and excess in superficiality. Weakness of spleen and stomach is the core pathogenesis. Clinical treatment should focus on regulating the spleen and stomach while ensuring the free movement of liver qi. The treatment mainly involves tonifying deficiency， activating blood and resolving stasis， and clearing heat. Prescription-based syndrome differentiation mainly targets spleen （stomach） deficiency syndrome， liver-stomach qi stagnation syndrome，stomach yin deficiency syndrome，and stomach collateral blood stasis syndrome.