Abstract: The study focuses on the blockage of Escherichia coli in the recharge process of groundwater source heat pumps. Observing the migration and deposition of Escherichia coli in porous media pores through a self-developed sand layer particle migration sedimentation test system; Comparative experiments were conducted using quartz and glass beads as porous media. The results show that the quartz particles are uneven, poorly graded, and the biting force between particles provides a "warm bed" for the deposition of Escherichia coli. As a result, the pore water pressure showes a state of first increasing, then decreasing, and finally stabilizing.However, the glass bead particles have a uniform particle size, and the particles are smooth and have low biting force, which is not conducive to the deposition of Escherichia coli, resulting in a sharp decrease in pore water pressure. Establish a mathematical model for the attenuation of Escherichia coli permeability, fit theoretical values with indoor experimental values, and verify that the proposed permeability attenuation model is effective in predicting the porosity decrease caused by microbial migration and deposition.