The extracellular matrix (ECM) remodeling represents the pathological substrate of dilated cardiomyopathy (DCM). In this study, we statistically analyzed the immunoexpression of collagen I and III, matrix metalloproteinase-1 (MMP-1) and its tissue inhibitor-1 (TIMP-1) in the myocardial tissue in 18 cases of DCM compared to a control group. We observed a significant increase in the immunoexpression of collagen I and III in patients with DCM and a significant reduction in the immunoexpression of MMP-1 compared with the control group. Also, the collagen I and TIMP-1 expression indicated a positive linear correlation and respectively a negative linear relationship with collagen III and MMP-1. The analyzed markers in this study can be used to quantify the degree of collagen sclerosis from the ECM of DCM.