This paper presented the development process and applicable conditions of the classical seepage mechanics theory- Darcy’s law, and derived the mathematical expressions of Darcy’s law in capillary seepage and fracture seepage in porous media from the Navier-Stokes (N-S) equations. The paper pointed out eight major problems in the current application of Darcy’s law and comprehensively analyzed the main challenges of seepage mechanics theory in oil and gas field development. In response to these challenges, this paper proposed a series of countermeasures and considerations. The paper emphasized that constructing multiscale, multi-physics field coupling models and leveraging AI scientific computing is the only way to reveal the complex and real flow mechanisms of oil and gas reservoirs and fill the current theoretical gaps. It was suggested to further develop high-precision experimental techniques such as nuclear magnetic resonance, electron microscopy scanning, and intelligent data and image processing to visually demonstrate the behavior and processes of fluids in reservoirs. Finally, it was suggested to use experimental research, the establishment of new theoretical models and AI for Science to innovate and break through the current challenges in the theory of oil and gas seepage mechanics. It provided an important reference for universities, research institutions and researchers to carry out theoretical research and project establishment of petroleum science, and it can also provided strong technical support for the scientific and technological development strategic planning of oil and gas resources in China.