Abstract: After more than 10 years of theoretical innovation and engineering practice in shale gas fracturing, supporting the scale cost-effective development of marine shale gas, China has established a theoretical and technical system for marine shale gas fracturing in the middle and shallow layers (< 3 500 m). The technically recoverable resources of deep (3 500-4 500 m) and ultra deep (> 4 500 m) shale gas in China account for 56.63% of the total recoverable shale gas reserve. To achieve efficient gas exploitation is essential for the development of the shale gas industry and guarantee of oil and gas security. The recoverable resources of deep (3 500-4 500 m) and ultra deep (> 4 500 m) shale gas in Sichuan Basin and its periphery account for 65.8% of the total reserve, making the most important contribution to the efficient development of shale gas and the construction of "Daqing Gas Base". Based on the preliminary exploration and practical understanding of deep and ultra deep shale gas fracturing in China and according to the 10 characteristics of deep and ultra deep shale gas fracturing, this paper analyzes six basic problems or challenges that are derived from above situation and urgently need to be solved. Further, the paper proposes five key theories and methods that urgently need to be innovated, points out 10 development directions for deep and ultra deep shale gas fracturing, and emphasizes that China's shale gas development should focus on both deep and shallow layers and continue to improve large-scale production and EOR in the middle and shallow layers. There are both opportunities and challenges in advancing into the new fields of exploration in deep and ultra deep layers to achieve efficient development. It is still necessary to continuously enhance the research, and accelerate the establishment of China's fracturing theory and technology system for deep and ultra deep shale gas.