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In this research, hematite (α-Fe₂O₃) nanoparticles with novel surface- modified were synthesized using iron (III) chloride hexahydrate (FeCl₃.6H₂O) and oleic acid (C₁₈H₃₄O₂) as raw materials by hydrothermal method at 250°C. The structural analysis such as XRD, FT-IR, SEM, TEM and BET showed the distribution of the synthesized nanoadsorbent, so that more (>90%) nanorod structures (diameter of 30-60 and length of 400-700 nm) were among the less nanoscaly crystals with 40-100 nm as thickness. The high specific surface area of the novel synthesized hematite nanoparticles (31.29 m²/g) determined their high capability for the removal of lead ions (Pb²⁺) from aqueous solutions. The adsorption of lead ions onto the synthesized nano α-Fe₂O₃ was investigated by pH, adsorbent weight, lead ions concentration, and contact time in batch experiments and initial condition of 25±1°C, 120 rpm, so that the optimum conditions for lead ions adsorption was obtained. On this basis, the removal of lead ions increased with an increase in pH; the optimum solution value was about 6.5 due to the bothersome hydroxide constructions in higher pH values. The analysis of equilibrium data showed that the Langmuir isotherm model is suitable for describing the lead ions adsorption by nano α-Fe₂O₃. Furthermore, the maximum sorption capacity of Pb²⁺ was estimated to be 111 mg/g. The kinetic of lead ions adsorption onto the synthesized nano α-Fe₂O₃ was best fitted by the pseudo-second order model known as Ho model. As adsorption optimum condition, the maximum upatake capacity of 49.31 mg/g was recorded along with the efficiency of 98.62% for the remove of Pb²⁺ ions from aquoes solution (1 mg/g), using 20 mg/L nano α-Fe₂O₃ adsorbent at 4 hour contact time. From these results, it can be concluded that the synthesized α-Fe₂O₃ surface-modified nanoparticles is a promising and effective adsorbent to remove lead ions as a heavy metal pollutant from aqueous solutions.