Abstract: Enhanced gallium nitride (GaN)-based high electron mobility transistor (HEMT) is a research hotspot in the field of high-frequency, high-power devices and switching devices. Thanks to its simple, controllable and repeatable fabrication process, P-GaN gate technology has become the most commonly used and the only commercially available technology for the fabrication of GaN-based enhanced devices. First, the primary problems restricting the development of P-GaN gate structure GaN-based HEMT device were summarized, then the latest research progress on performance optimization was reviewed from the aspect of structure and fabrication process. By analyzing the research progress, challenges and solutions of current research work were concluded. Finally, the future development prospects and trends were prospected briefly.