Local thermal ablation treatment of tumor is a hot topic of research at home and abroad in the past 10 years. This method mainly involves the introduction of certain energy into the body under the guidance of images and acting on tumor tissues to make the temperature of the treatment area reach 60℃ (immediately) or 54℃ (3 minutes), resulting in irreversible coagulative necrosis of tissue cells, so as to achieve the purpose of treating tumor. Among various thermal ablation methods, the most widely used ones at home and abroad are radiofrequency ablation and microwave ablation. In addition to the advantages of other thermal ablation techniques, microwave ablation also has the characteristics of not being affected by current conduction, less affected by carbonization and blood perfusion, fast temperature rise, large ablation range, etc. 1.Ablation of tumor size: Multi-polar RF adopts the form of electrode with umbrella-like multi-claw, which aims to effectively expand the ablation range and change the shortcomings of small ablation range of monopolar RF. At present, the theoretical maximum ablation range of imported multi-pole RF is about 5cm. After years of development and improvement of microwave ablation, the actual ablation range of single needle of 2450MHz instrument has been stabilized above 5cm, and the actual ablation range of single needle of 915MHz instrument is up to 8cm. 2. Ablation time: In the case of ablation of the same size tumor, the microwave basically needs only about half of the time of multi-polar radio frequency. However, multi-polar radiofrequency has to open and retract the umbrella electrode several times, so this process will greatly increase the operation time. Therefore, the operating time of microwave is much better than multipolar RF, which can effectively reduce the risk of anesthesia and other unnecessary surgical risks. The above two points have been widely recognized in the international arena. 3, the complexity of electrode puncture operation: first of all, microwave electrodes do not need Pad (negative plate), while multi-polar radio frequency must be in the patient’s thigh or hip Pad in place or not directly affect the ablation range of multi-polar radio frequency. And it is required that the patient should not have the instrument for heart use in the body. Secondly, compared with the microwave electrode, multipolar radiofrequency has to open and retrieve the electrode repeatedly, which greatly increases the complexity of the operation. In addition, because of the different quality of tumor tissues, the shape of electrode cannot be as perfect as opening in air, so it is bound to affect the ablation shape. 4. The risks of the two ablation methods are different under the existing influencing guidance methods: Nowadays, the guidance methods, no matter CT, ultrasound or other methods, are guided under 2D images. The single needle electrode of microwave has no risk at all under 2D image. In contrast, the umbrella electrodes of multipolar radiofrequency are open in three dimensions, so the surgeon cannot fully brace the extension direction of all electrodes under 2D images. In the case that the tumor is adjacent to several organs or the blood vessels are more complicated, multi-polar radiofrequency has more risks and more contraindications to the surgery. 5, other factors affecting the effect of surgery: firstly, the ablation temperature of RF is lower than that of microwave, so it is greatly influenced by the blood supply, so it is internationally recognized that the ablation boundary of microwave is smooth and clear, while the ablation boundary of RF is mostly jagged, which is not as clear as microwave and is not conducive to post-operative evaluation; secondly, multi-polar RF is only suitable for deep solid tumors influenced by Pad, while microwave electrode can also be used for superficial tumor treatment because it is monopolar. It can be used for the treatment of superficial tumors.