Objective To investigate the feasibility and significance of joint microwave ablation for simultaneous treatment of two or more benign neoplasms originating from different organs which are conventionally managed in different disciplinary offices. Methods We treated a middle-aged female patient suffered with a large thyroid adenoma and a huge liver cavernous hemangioma with microwave ablation under local anesthesia and general anesthesia consecutively in one treatment session. The safety of operation and dynamic therapeutic effect were assessed. Results The thermal ablation procedures were both successful and eventful. The total operation time was about 90 minutes. The patient was discharged on the third day after ablation. During the follow-up, ultrasonography revealed a significant shrinkage of thyroid adenoma and liver hemangioma and recovery of the perinodular thyroid or liver tissue. The laboratory tests showed functional abnormalities of neither the thyroid, nor the liver and kidney. Conclusion: Joint microwave ablation for simultaneously treating large thyroid adenoma and huge liver cavernous hemangioma was verified safe, efficacious and medical resources sparing. This innovative therapeutic concept is worth of further investigation and promotion.