The waste biomass of e-Poly-L-lysine fermentation was investigated for hexavalent chromium [Cr (VI)] removal. The effect of pretreatment on the biosorption capacity of Cr (VI) ions onto fermentation waste biomass using several chemical agents were initially studied 1 mol/L HCl gave the maximum enhancement of the Cr (VI) uptake. The influence of solution pH, initial metal concentration, contact time and biomass dosage were studied. The biosorption process was affected markedly by the pH and initial metal concentration of the solution. Adsorption isotherms were modeled with the Langmuir and Freundlich equations and isotherm constants were calculated. Biosorption of Cr (VI) onto acid-treated waste biomass of Kitasatospora sp. MY 5-36 and Streptomyces albulus PD-1 followed the Langmuir isotherm model with the maximum biosorption capacity of 61.22 mg/g and 70.61 mg/g was achieved. The biosorption mechanisms have been investigated involving fourier transform infrared spectroscopic (FT-IR) and transmission electron microscopy and electron-dispersive X-ray (TEM-EDX) studies. The present investigation suggested that the two strains have great potential to act as a biosorbent for the removal of Cr (VI) from waste water, especially S. albulus PD-1 which was better than K. sp. MY 5-36 in terms of biosorption performance, efficiency, and cost reduction.