Abstract: To improve the fracturing efficiency and reduce the fracturing cost, the testing of dual-well simultaneous fracturing was performed for four-well pads of Mahu. Specifically, the fracturing operation was performed simultaneously using the same group of fracturing trucks for two wells of a multi-well pad containing four or more wells. Compared with the conventional zipper fracturing operation with the same hydraulic horsepower in the same block, the testing presents a time reduction of well completion by 45% and the growth of the daily average operation efficiency by 70%. However, geologic, engineering and equipment factors resulted in the failure to synchronize well fracturing, the design with only two perforation clusters in one fracturing stage led to perforation plugging and abrupt rising of operation pressure, and the failure and movement of bridge plugs caused sudden drops of treatment pressure. Analysis of the current challenges indicates that the practice of dual-well simultaneous fracturing requires more work in planning well placement and drilling operations, upgrading core equipment and optimizing the perforating scheme, to form a dual-well synchronous fracturing technology template suitable for domestic unconventional oil and gas development.