Background: lung cancer (LC) is the fifth of the 10 leading causes of death in the world. LC is in first placefor cancer-related mortality for both males and females in Taiwan. It is one of the most difficult cancers to treatand is often diagnosed at a late stage. Patients with stage IV are often unprepared for the diagnosis. Materialsand Methods: To explore lived experience among patients newly diagnosed with lung adenocarcinoma stage IVwithin one year. Results: Twelve participants were recruited in this study. Content analysis of the interviewsrevealed four themes: (1) emotional roller coaster, (2) trying to find out causes, (3) adjusting my lifestyle, and(4) cancer fighter. Conclusions: This study provides new insight into the experiences of lung cancer patients ywith newly diagnosed lung adenocarcinoma stage 4. These results will inform future supportive care servicedevelopment and intervention research for patients with advanced stage cancer.