[Objective] Phenol is a common organic pollutant that comes along with wastewater discharged from chemical industries. Clay minerals are abundant in reserve and high in adsorptivity, and hence have good prospects in application as adsorbents. The technology of magnetization and amphoteric modification can keep clay minerals capable of adsorbing organic and heavy metal pollutants and separating solid from liquid as well, which is conducive to material recycling. However, so far little has been reported about researches on comparison between different types of magnetized and modified clay minerals in adsorption of phenols and its mechanism, which though has certain practical significance for the application of amphoteric modified magnetic clay minerals to treatment of organic wastewater pollution.[Method] Magnetic sepiolite (MST), magnetic zeolite (MZT) and magnetic attapulgite (MAT) were prepared using the co-precipitation method, and then modified separately with the amphoteric surfactant dodecyl dimethyl betaine (BS-12). X-ray diffraction (XRD) was performed to characterize these adsorption materials, and then batch method was adopted to compare the three BS-12 modified magnetic clay minerals in phenol adsorption characteristics, while effects of temperature, pH, ionic strength and modification degree on the clay minerals adsorbing phenol were also investigated.[Result] Results show that in terms of phenol adsorption capacity of the three natural clay minerals and the three magnetized clay minerals exhibited an order of NAT > NST > NZT, and MAT > MST > MZT, respectively, and magnetization had the highest effect on the phenol adsorption capacity of attapulgite, which is highly related to the high Fe₃O₄ coverage on attapulgite. Once modified with BS-12, the three modified magnetic clay minerals increased in phenol adsorption capacity with increasing modification degree, showing a consistent trend; Among the three magnetic clay minerals, magnetic sepiolite increased the most phenol adsorption capacity in response to the BS-12 modification, which is related to its higher BS-12 modification rate. The increase in temperature or pH was not conducive to phenol adsorption on the BS-12-modified magnetic clay minerals, but the increase in ionic strength did have some positive effect.[Conclusion] Phenol adsorption on BS-12-modified magnetic clay minerals is dominated by hydrophobic partitioning, and phenol adsorption capacity of the minerals depends on organic carbon content. Among the three BS-12 modified magnetic clay minerals, BS-12 modified magnetic attapulgite has the highest phenol adsorption capacity as it has the highest organic carbon content, and it capacity is rarely affected by temperature, pH and ionic strength.