Background: Non-small cell lung cancer (NSCLC) accounts for the majority of all lung cancer cases. Causes of NSCLC are typically identified through molecular testing for EGFR and other mutations. Around half of Asian patients with NSCLC, particularly non-smoking women, have EGFR mutations. Most patients with ipsilateral NSCLC typically have a single common EGFR mutation in exons 18-21. It is extremely rare for patients with bilateral primary NSCLC to harbor two different EGFR mutations. Case summary: We present a 70-year-old non-smoking Vietnamese patient diagnosed with early bilateral primary NSCLC with the presence of EGFR in both exon 18 and exon 19. The complexities of diagnosis and treatment for this case resulted in surgical intervention on the left lung and targeted therapy with afatinib for the right lung. Progression arrest was observered in a period of 12 months. Conclusion: This case highlights a rare instance of synchronous bilateral NSCLC in a non-smoking, 70-year-old Vietnamese woman with complex management, underscoring the challenges of treating synchronous primary tumors with different genetic profiles.