Surgical resection plus postoperative whole brain radiation therapy (WBRT) has proven to be one of the best management combinations for metastatic brain tumors. However, WBRT could be related to and might even induce the deterioration of the cognitive function and quality of life. In this study, author group investigated the effectiveness and safety of gross total resection without consecutive postoperative WBRT for single or two brain metastases. Illustrative case showed serial MRI images of a 58-year-old male patient with non-small cell lung cancer, who underwent tumor resection and planned observation: preoperative image (left-upper); postoperative 3 months (right-upper); 1-year follow-up (left-lower); 4-year follow-up (right-lower).