<p>This study aimed to investigate the simultaneous removal of heavy metals (Cr(VI), Cu(II), Ni(II), and Zn(II)) from electroplating wastewater using tea factory waste as an adsorbent. The effects of parameters such as adsorbent particle size, dosage, contact time, initial pH, and temperature on the removal efficiency of these metals from synthetic wastewater (a mixture of the studied metals) were explored in a multi-metal system. Experimental data were analyzed using Langmuir, Freundlich, and D-R isotherm models. The maximum adsorption capacities (<i>q</i>_<i>max</i>) were found to be 3.68 mg/g for Cu(II) and, 3.22 mg/g for Ni(II). The order of metal adsorption followed: Cr(VI) &gt; Cu(II) &gt; Zn(II) &gt; Ni(II). Thermodynamic parameters were also calculated, with negative <i>ΔG</i> values indicating that the process is spontaneous, while positive <i>ΔH</i> values suggested that the reaction is endothermic. The findings of this study demonstrate that tea factory waste has the potential to act as an effective adsorbent for the simultaneous removal of heavy metals from real electroplating wastewater.</p> Graphical Abstract <p></p>