Induced polarization method has become a popular method for evaluating formation permeability characteristics in recent years because of its sensitivity to water body and water-bearing pore structure. Especially, the induced polarization relaxation time can reflect the macroscopic characteristics of the pore structure of rock and soil. Therefore, in order to study the relationship between relaxation time and permeability, eight different sizes of quartz sand were used to simulate water-bearing sand layers under different working conditions, and the induced polarization experiment and Darcy seepage experiment were carried out on the same sand sample in this paper, respectively. The experimental results show that the relation time and the evolution of the permeability are closely correlated with the sizes of quartz sand. According to the experimental data, with the particle size of the quartz sand as the link, the power function equation is fitted to better describe the relationship between the permeability and the relation time. It is worth noting that the equations obtained are only empirical equations for quartz sand and are not suitable for general applications.