Whether chemotherapy is needed after surgery for stage 1b invasive lung adenocarcinoma needs to depend on the specific condition. For patients with stage 1b invasive lung adenocarcinoma, if the surgery is complete resection of the resected lesion and the lesion does not involve the pleura, vasculature, nerves, etc., no chemotherapy can be given after surgery. For patients with stage 1b lung adenocarcinoma with high risk factors, such as poorly differentiated tumors, vascular invasion, wedge resection, pleural invasion of the dirty layer, and unknown lymph node status. In such patients, postoperative chemotherapy under physician’s supervision is needed to further reduce the risk of recurrence. It is recommended that patients choose the appropriate treatment plan according to their specific condition under the guidance of their physicians.