A synthetic clay (Mg/Al-layered double hydroxides; LDH) was directly synthesized through a simple coprecipitation method under a low-supersaturation condition. The clay was applied to remove metal cations (Cd²⁺, Cu²⁺, Pb²⁺, Ni²⁺, and Cr³⁺) and oxyanions (MnO₄^– and Cr₂O₇^2–) from a single aqueous solution. The result demonstrated that LDH exhibited a poor porosity (its specific surface area and total pore volume: 23.2 m²/g and 0.161 cm³/g, respectively) and positively charged surface within solution pH from 3.0 to 12. The X-ray powder diffraction (XRD) data suggested that the basal spacing of LDH was 0.773 nm. The presence of active CO₃^2– anions in the interlayer region of LDH that played an extremely important role in the adsorption process was identified by XRD and Fourier-transform infrared spectroscopy (FTIR). Energy-dispersive X-ray spectroscopy (SEM) analysis indicated that LDH possessed a surface morphology like a plate with a hexagonal shape. The adsorption isotherms of LDH towards various potentially toxic metals were conducted at 1.0 g/L, pH_Equilibrium 5.0, 30°C, and 24 h. The Langmuir maximum adsorption capacity of LDH towards the target metals exhibited the following order: 1.299 mmol/g (for Ni²⁺ adsorption) > 0.880 mmol/g (Cd²⁺) > 0.701 mmol/g (Cr³⁺) > 0.657 mmol/g (Pb²⁺) > 0.601 mmol/g (Cu²⁺) > 0.589 mmol/g (Cr₂O₇^2–) > . The synthetic clay can adsorb both cations and anions in the solution. Therefore, such LDH material can serve as a potential dual-electronic adsorbent for effectively eliminating various oxyanionic and cationic metal ions from water media.