A novel germline transmission of the epidermal growth factor receptor (EGFR) mutation V843I in a family with multiple members with lung cancer is reported. The proband was a 70-year-old woman with multiple adenocarcinomas who exhibited secondary EGFR mutations, either L858R or L861Q, in the specimens of resected tumors, in addition to a germline EGFR V843I mutation. These observations suggest that the germline EGFR V843I mutation might have altered EGFR signaling in the multicentric development of adenocarcinoma, bronchoalveolar carcinoma, and atypical adenomatous hyperplasia and also might have had a role in the development of lung cancer in multiple members of her family.