The biosorption process and agricultural waste to treat heavy metals has drawn much attention. This method seems to be a more economical, envchromiummentallyfriendly, and simple way for removing heavy metals from effluents. The study was conducted to explore the efficiency of the biosorption process utilizing rice husk to remove Pb²⁺ and Cr³⁺ from synthetic wastewater. Biosorption studies at different operating parameters, such as biosorbent dosage (0.5-5.0 g), pH (pH2–8), contact time (15-120 minutes), and initial heavy metal concentration (10-100 mg/L), were conducted in batch experiments. The highest performance for Pb²⁺ and Cr³⁺ biosorption was found at 5.0g biosorbent dosage of spent mushroom compost, unadjusted pH 6, 10 minutes of contact time, and 10 mg/L of initial concentration. The study was well fitted to the Langmuir isotherm model (R²> 0.90) for Pb²⁺ and Cr³⁺ biosorption, which are much greater compared to the Freundlich model.Solvent of 0.1N Sulphuric acid showed higher desorption of Pb²⁺(89%) and Cr³⁺(86%) adsorption-desorption process can be continued till seven cycles efficiently.In conclusion, the rice husk has the potential to be an effective biosorbent for removing Pb²⁺ and Cr³⁺ from synthetic wastewater.