There are currently many materials for treating residual antibiotics in the environment, but none of them can specifically remove antibiotics. In addition, these materials are not sensitive enough to low concentrations of antibiotics. Here we show that a sensitive and specific material was developed by the preparation of magnetic Fe₃O₄-PAMAM-antibody complexes for treating tetracycline. The prepared antibody complexes can specifically treat tetracycline from aqueous solutions and the tetracycline removal ability by adsorption was also investigated. Controlled experiments were carried out with the effects of solution pH, temperature, and initial concentration of the tetracycline. The tetracycline was completely removed within 35 min at room temperature 30 °C with the maximum removal rate of almost 100%. Therefore, this material for specifically combining antigen and antibody to treat tetracycline indicated good application prospects for the waste water treatment.