After entering the reservoir as a thickening agent for fracturing fluid, polyacrylamide will undergo adsorption and retention with rocks, leading to a reduction or even complete blockage of oil and gas flow channels, resulting in poor efficiency in reservoir stimulation and transformation. This paper takes dense sandstone as the research object, and through joint testing of core permeability damage and adsorption retention, studies the influence of flow conditions (displacement time, displacement rate, backflow rate, backflow time) on the adsorption retention damage of polymer fracturing fluid, and analyzes the influence mechanism of flow conditions on the polymer adsorption retention process. The results show that the degree of adsorption retention damage gradually increases with the increase of displacement time, reaches equilibrium after 100 min, and the maximum damage degree is 24.1%; As the displacement rate increases, it first increases and then stabilizes, with 12 mL/min being the critical displacement for indoor adsorption retention experiments; As the reflux rate increases, it decreases, and the longer the reflux time, the lower the degree of damage caused by adsorption retention.