【Objective】Veterinary antibiotics are extensively used in livestock rearing industries all over the world for preventive and therapeutic treatments and growth promotion of poultry and/or animals. Due to the use of chemical fertilizers and compost, pollution from the industry and/or irrigation with sewage, etc., the content of heavy metals in the soil is getting higher and higher. It is, therefore, often found that the two kinds of pollutants, antibiotics and heavy metals exist simultaneously in the soil, affecting each other in adsorption and migration. Their pollution of the soil has become an environmental issue that can’t be ignored. Therefore, investigation of leaching and adsorption behaviors of these antibiotics and heavy metals in the soil is the first logical step to assess their ecological risks and then develop corresponding pollution control strategies.【Method】 In this research, the soil was exposed to different concentrations of Cd, Cu and Pb. Effects of the pollutants on adsorption and migration of Sulfadiazine (SDZ) in the soil were studied via both batch and column experiments. Adsorption isotherm of SDZ was fitted with Freundlich, Langmuir and Linear models and breakthrough curves of SDZ with the coexisting heavy metals were measured and modeled using numerical models that took into account reversible and irreversible kinetic sorption sites with the aid of the Hydrus-1D software.【Result】No influence of Cd was found on adsorption of Sulfadiazine, when Cd was 100.0 mg·kg^-1 in concentration, but it did promote the adsorption of SDZ when 10.0 mg·kg^-1 in concentration, and reduce the adsorption of Sulfadiazine, when 1.0 or 300.0 mg·kg^-1 in concentration. When Cu, Pb and Cd, all 300.0 mg kg^-1 in concentration, coexisted with SDZ, they displayed an order of Cd > Cu > Pb in effect on SDZ adsorption of Sulfadiazine. In the soil column leaching experiment, it was found that Cd, 10.0 mg·kg^-1, slowed down the migration of SDZ, while no significant effects were found with Cd higher or lower in concentration. Comparison between the three elements shows that Cu promoted and Cd slowed down the migration of SDZ. The Linear equation was the best in fitting, with R² being above 0.98. Compared with the OSM model, the TSM model simulated better the migration process of SDZ, with R² >0.907 and RMSE <0.051. Instantaneous adsorption (f) was found quite high in the process of sulfadiazine migration. 【Conclusion】 Under complex pollution of SDZ and heavy metals, adsorption and migration of SDZ is affected by type and concentration of the heavy metal in the soil. The findings in this study may not only help improve knowledge of the mechanisms of adsorption and transport of SDZ in heavy metal contaminated soils, but also serve as a certain theory basis for management of environmental pollution.