Batch mode experiments were carried out for the removal of Reactive Orange 107 from aqueous solution using native and dead mycelia pellets/biomass of Alternaria raphani. The effect of process parameters like contact time, dosage of adsorbent, adsorbate concentration and pH on adsorption was investigated. Higher the dye concentrations lower the adsorption. Increase in biomass dosage increased the adsorption. Experimental data were analyzed by the Langmuir and freundlich isotherms. Adsorption capacity (Qo) of autoclave biomass was 28.74mg/g, which was higher than native biomass studied. The second-order kinetic model by Ho and Mckay described well the experimental data. Acidic pH was favorable for the adsorption of RO 107. Studies on pH effect and desorption show that chemisorptions and physisorption play a major role in the adsorption process. Among the biomass studied, autoclaved biomass showed a better adsorption capacity. Utilization of autoclaved biomass is much safer as it does not pose any threat to environment. These results suggest that this fungus can be used in biotreatment process as biosorbent for reactive dyes.