Cancer is an increasingly serious risk to human health, and its incidence and mortality rates have been increasing rapidly worldwide since the mid-20th century. According to information published by the World Health Organization, cancer accounted for 7.6 million (or 13%) of all deaths in 2005, out of a total of 58 million deaths worldwide. In China, the incidence and mortality rates of cancer have increased significantly compared to the 1970s in both urban and rural areas. The majority of cancer patients are already in the middle and late stages when they are seen, and only 20%-30% are able to be treated surgically. Despite the current progress in multidisciplinary comprehensive treatment, the overall cure rate and 5-year survival rate are still less than 15%. Seeking more effective and less invasive treatment methods has become a common concern, and in recent years, new minimally invasive or non-invasive treatment techniques have become a hot spot in malignant tumor treatment. For hepatocellular carcinoma, microwave ablation is a very effective thermal therapy method, which shows many advantages over other procedures. First, it has the common advantages of thermal ablation procedures, such as: repeatable treatment, predictable ablation size and good reproducibility. Second, compared with the current common use of radiofrequency ablation, microwave ablation has several theoretical advantages: First, microwave ablation has a very wide active heating area that does not depend on tissue conductivity, and the transmission of microwave energy in living tissue is not limited by tissue drying and charring. Therefore, the intra-tumor temperature can reach a high enough level to ensure the creation of a large enough ablation area to inactivate the tumor more completely in a shorter treatment time. Second, the cooling effect of blood flow can significantly affect the ablation of the effective heating area, but microwave ablation is less affected by the “heat drop” effect of the perfusion medium, so that it can better inactivate tumors close to blood vessels. Third, the electron interference phenomenon present in RF ablation does not occur when multiple microwave energies act synergistically, which can easily expand the scope of tumor ablation in a short period of time through synergistic effects.