In response to the frequent wellbore instability issues encountered during drilling operations in complex shale formations，the drilling fluid technologies aimed at wellbore stabilization have been developed at home and abroad. These include shale hydration inhibition，formation pore plugging，and chemical wall strengthening techniques. Despite these advancements，existing methods have limitations in curbing the surface hydration of shale，and the effect of rapid plugging and wall strengthening agent is considerably reduced under high temperature conditions，making it challenging to address wellbore instability. This paper offers a comprehensive review of the research work on drilling fluid materials for wellbore stability in complex shale formations. By analyzing the current state of research，it elucidates the mechanism of various drilling fluid materials，including shale hydration inhibitors，plugging agents，and chemical wall strengthening agents. It also discusses the strengths and limitations of different types of wellbore stabilization materials. This paper highlights the need for fundamental theoretical research into shale hydration，the development of novel nanomaterials that are stable and effective under high temperature and high salinity conditions，and the establishment of evaluation methods for chemical wall strengthening agents that can simulate downhole conditions. These areas are identified as key focal points and challenges for future research in the field of drilling fluid materials and technologies for wellbore stabilization in complex shale formations. This paper concludes with an outlook on the future development directions for these technologies and materials.

To prevent the water block damage induced by any extraneous fluid's invasion during drilling and completion operations in low-permeability gas reservoirs，a high-performance anti-water blocking agent（FWB），which is composed of hydrogen-rich block silicone oil and some additives such as organosilicon surfactant and deformer，was developed for low-permeability gas reservoirs. The infrared spectroscopy was used to characterize the molecular structure of the block silicone oil，and a series of tests，which include surface tension test，contact angle test，core imbibition test，permeability recovery ratio test，and drilling fluid compatibility test，were conducted to comprehensively evaluate the performance of this anti-water blocking agent. The test results show that，at the mass concentration of 1%，it can dramatically reduce the surface tension of the aqueous phase to 22.28 mN/m，increase the contact angle of the aqueous phase from 29° to 120°，decrease the core imbibition amount by 69.2%，and improve the permeability recovery ratio to 89.3%，and that it has good compatibility with drilling fluids. This anti-water blocking agent can significantly reduce the water block damage during drilling and completion operations and provide effective protection for low-permeability oil and gas reservoirs.