Thermal ablation of lung tumors is a safe and effective, minimally invasive treatment option for patients with stage Ia NSCLC or pulmonary metastases, especially from colorectal cancer if surgical resection or stereotactic radiation therapy is not an option. Alternative indications include local recurrences after thoracic surgery or stereotactic radiotherapy. Percutaneous image-guided MWA shows promising clinical results with limited side effects. Most complications can be classified as minor complications and be managed by minimal invasive treatment. Therefore, MWA of malignant lung tumors should be part of the interventional oncology toolbox of interventional radiology in all oncological centers taking care of patients suffering from NSCLC and colorectal cancers.