Myocardial fibrosis is a key pathological change in the progression of cardiovascular diseases such as heart failure. The progression mechanism of this disease relies on the reciprocal regulation between macrophages and fibroblasts. Current modern medical research has confirmed that macrophages can mediate inflammatory responses and tissue repair processes through M1 and M2 phenotypic polarization behaviors, and fibroblasts can differentiate into myofibroblasts and promote abnormal extracellular matrix deposition. The two types of cells can construct a reciprocal regulatory network through signaling pathways such as TGF-β/Smad and CSF-1/CSF-1R, thereby mediating the deterioration of myocardial fibrosis. The theory of phlegm and blood stasis intermingling in traditional Chinese medicine suggests that phlegm turbidity and blood stasis can mutually generate and interweave to cause obstruction, serving as a key pathological basis for various chronic and persistent diseases. This article takes the traditional Chinese medicine theory of phlegmblood stasis intermingling as a research entry point, analyzes the intrinsic relationship between this pathological theory and the interaction of macrophages and fibroblasts, integrates existing modern medical research findings on the interaction between the two cell types, and deeply analyzes the synergistic mechanisms and pathological correlations of cellcell interactions in the pathogenesis of myocardial fibrosis. The aim is to provide a theoretical basis for the integrated traditional Chinese and Western medicine prevention and treatment of myocardial fibrosis, and also to lay a solid research foundation for related animal experiments and clinical application studies.