Background and Purpose: Epidermal growth factor receptor (EGFR) is considered as a valid target in the clinical trials of anticancer therapy and tyrosine kinase inhibitors (TKIs) of EGFR are approved for cancer treatments. Experimental Approach: A549 cells proliferation, apoptosis, and cycle analysis were measured by MTT, annexin V-FITC apoptosis, and PI-staining assay, respectively. Meanwhile, the accumulation levels of the gene and protein were carried out by real-time quantitative PCR and western blotting assays. The inhibiting effect of CuIIb against the phosphorylation level of the EGFR protein was detected by homogeneous time-resolved ﬂuorescence (HTRF) analysis. Based on molecular docking, the binding interaction of CuIIb with EGFR was evaluated. Key Results: CuIIb was confirmed to exhibited the proliferation inhibitory activity in A549 cells. CuIIb induced apoptosis via STAT3 pathway and arrested the cell cycle in G2/M phase. HTRF analysis demonstrated the kinase activity of EGFR was inhibited by CuIIb. The results of molecular docking suggest that the CuIIb-EGFR binding fundamentally depends on the contribution of both hydrophobic and hydrogen-bonding interactions. Conclusion and Implications: CuIIb was capable of suppressing the signal transmitting of the EGFR/MAPK pathway by severely reduced the amounts of the most participants in the pathway and inhibited the activation thereof, thus suppression of EGFR/MAPK signaling pathway was responsible to the apoptosis and cell cycle arrest. In addition, CuIIb may serve as a potential EGFR TKI.