Paleopathological evidence of cancer from past populations is rare, especially outside of Europe and North Africa. To begin to fill the gaps in the geographical distribution of neoplastic disease, this study presents a probable case of multiple myeloma in an adult male from the Qijia culture horizon (1750-1400 BCE) of the Bronze Age cemetery of Mogou ( 磨 磨 ), located in Gansu Province, Northwest China. Multiple ovoid-shaped osteolytic lesions with sharply demarcated margins were assessed macroscopically and radiographically. The axial skeletal had the greatest involvement, specifically the vertebrae, ribs, and sternum. Radiographic imaging revealed more extensive destruction of hematogenous than cortical bone, indicating that the marrow was the focal point of the disease. Based on the nature, distribution, and radiographic appearance of the lesions, the most likely diagnosis is multiple myeloma. This is one of the only cases of cancer identified in archaeological human skeletal remains in East Asia. By placing case studies such as this into a temporal and spatial framework, it is possible for future research to begin to interrogate possible underlying causes of cancer in ancient populations within the context of changing environmental conditions and subsistence strategies.