In this paper, the efficiency of biosorbent prepared from Mikania micrantha to remediate a hazardous dye Alizarin Red S from aqueous phase was investigated. Morphological and constitutional characteristics of the biosorbent were studied by performing SEM and FTIR. The adsorption equilibrium was modeled with the Langmuir and Freundlich isotherm. The maximum monolayer adsorption capacity was found to be 46.51 mg g(-1) at 50 degrees C. The isotherm data were better fitted to Freundlich model indicated heterogeneous nature of the adsorbent. The negative values of Delta G degrees and positive value of Delta H degrees demonstrated that the adsorption of Alizarin Red S onto Mikania micrantha were spontaneous and endothermic in nature, respectively. Positive value of Delta S degrees advocated the randomness at solid-liquid interface.