The pollution of tetracycline antibiotics in the water environment is increasingly serious, and the effective removal of residual antibiotics in water is an urgent problem to be solved. The co?precipitation method was used to prepare Cu?Al layered double hydroxides biochar composites (CuAl?LDH@BC) intending to remove tetracycline hydrochloride (TCH) from water. The physicochemical properties of the CuAl?LDH@BC surface were analyzed by SEM, XRD, and FTIR, and the adsorption performance of the tetracycline hydrochloride solution was revealed. The experimental results show that the adsorption process is more consistent with the quasi?second?order kinetic model and Langmuir model, and the maximum adsorption capacity of TCH is 78.68 mg/g at 298 K, and the neutral condition CuAl?LDH@BC has the best removal effect on TCH, which has strong anti?interference ability in water environment. The mechanisms involved in the adsorption of TCH by CuAl?LDH@BC may include hydrogen bonding, surface complexation, π-π interaction, and electrostatic interaction. The results show that Cu?Al layered double hydroxides and biochar composites, as low?cost and high?efficiency adsorbents, have a broad application prospect in the adsorption of tetracycline antibiotics in water.