Skeletal muscle metastasis of nonsmall cell lung carcinoma (NSCLC) is a rare occurrence, and the most effective treatment modality is currently unknown. In this case presentation, we report a patient with NSCLC who underwent palliative radiotherapy for biceps muscle metastasis of NSLCS. Our case was a 49-year-old woman who had lung adenocarcinoma with biceps muscle metastasis. She had been followed up for 2 years due to Stage IV lung adenocarcinoma from whom a biopsy was taken from a painful mass in right arm that was found to be compatible with metastasis of lung adenocarcinoma. She had palliative radiotherapy for her painful mass and systemic chemotherapy was planned. After palliative radiotherapy, the pain originating from the metastatic mass in right biceps muscle alleviated. Palliative radiotherapy can be a valuable treatment option for cases with skeletal muscle metastasis.