Statins exert a protective effect on lungs, inhibiting the proinflammatory MMPs induction crucial in the COPD pathogenesis. Objective. The aim of this study was to assess the effect of three‑month simvastatin treatment on selected MMPs concentration in blood serum, on lung function and clinical parameters in patients with stable COPD. Material and method. A prospective single‑center study was conducted in 39 males and 11 females (aged from 47 to 80) randomly allocated to two groups: the study group – receiving simvastatin (Zocor 40 mg) and the control group – not receiving the drug. Results. Finally, 26 patients in the statin group and 24 in the control group completed the study. No significant differences were found between the study group and control group in respect of mMRC results (p=0.6458), spirometry parameters measured with FEV1%N, FVC% N and FEV%FVC and in concentration changes of MMP‑1 (p=0.6468), MMP‑9 (p=0.0651) and MMP‑12 (p=0.3309). The treatment had a positive effect (p=0.0053) on the CAT results of COPD clinical course. Significant decrease in MMP‑1 concentration (p=0.0454) in the statin group in comparison with the control group was shown only in the subgroup of patients with FEV1<50%N. Conclusions. In stable COPD, Simvastatin treatment has no significant effect on decrease in serum concentration of specific MMP‑1, MMP‑9 and MMP‑12 crucial in the disease pathogenesis.