We herein report an NSCLC case with a novel <i>EGFR</i>ex20ins mutation D770_N771insGT and multiple brain metastases who briefly responded to first-line osimertinib treatment and subsequently achieved prolonged disease control with osimertinib plus bevacizumab as second-line treatment. The gene discussed is EGFR; the disease is non-small cell lung carcinoma.