The purpose was to investigate the efficacy and safety of Osimertinib in the treatment of advanced non-small cell lung cancer and to analyze its effects on the expression of serum matrix metalloproteinase-7 (MMP-7) and matrix metallo-proteinase-9 (MMP-9). Eighty patients were equally divided into observation and control group. The observation group was given Osimertinib combined with conventional chemotherapy and the other was treated with conventional chemotherapy alone. The short-term efficacy, the levels of serum MMP-7, MMP-9 and adverse reactions were compared. The effectiveness and clinical benefit rate of the observation group were 62.50% and 92.50% respectively, significantly higher than the control group. There was no significant difference in MMP-7 and MMP-9 before treatment however there was a significant difference after treatment, and the serum MMP-7 & MMP-9 levels showed a trend of increasing with decreasing efficacy. After treatment, comparing with control group, serum MMP-7 and MMP-9 levels were significantly lower, the Karnofsky score was significantly higher, and the improvement effect of the quality of life was statistically significant. Besides, the incidence of leukopenia, thrombocytopenia, anemia and gastrointestinal symptoms were significantly lower. In the treatment of patients with advanced non-small cell lung cancer, Osimertinib significantly reduced the expression of serum MMP-7, MMP-9, improved the clinical benefit and quality of life of patients. The clinical efficacy was significant with a high safety.