In this work, corncob waste was used as a solid adsorbent for removal of Pb, Ni, Zn, Cd ions from aquatic ecosystem through batch techniques. The influences of bio-sorbent dose, pH, concentration of metal ions and contact time with biochar on these heavy metal ions removal percentages were investigated. Optimum removal of Pb, Ni, Zn and Cd ions was achieved at bio-sorbent dose (3g), and contact time (90 min.). Desorption experiments were performed due to the importance for the financial competitiveness of biosorption with other process, indicating that (2.5 M) sodium hydroxide is the most promising desorbing agent for efficient sorbent regeneration. The results of this study confirm that corncob waste can be beneficially used for treating aquatic ecosystem containing Pb, Ni, Zn and Cd ions.