Treatment of dissolved mercury within water sources is crucial. This study reported the utilization and efficacy of chitosan-sulfide immobilized on dead corals (Acropora cervicornis) as an absorbent for dissolved mercury (II). Sulfide ions were immobilized on coral particles coated with chitosan (coral-Chi). Chitosan and sulfide were either mixed or stepwise immobilized on dead coral particles. The amount of mercury absorbed by this treated absorbent (coral-Chi-Na2S) was studied and compared to the control (coral only or coral-Chi). The adsorption process is a bath method within a chromatography column. The absorbent characteristics and the amount of mercury(II) absorbed were characterized. The results showed that the highest percentage of adsorption used adsorben coral-Chi-Na2S, which was 71% with an eluent flow of 0.5 mls-1 within the absorbent column. The capacity of adsorption ion Hg2+ after prior eluting in the column for 24 h contact time was 0.4057 mg/g, 0.4017 mg/g, and 0.3746 mg/g in coral-Chi-Na2S, coral, and coral-Chi respectively