Cinnamon-bark (Cinnamomum zeylanicum) powder (CP) was investigated to evaluate the As(III) biosorption capability from aqueous solution. Biosorption behavior of As(III) was studied by batch column experiments. The adsorption phenomenon were analyzed with various experimental variables such as solution pH, sorbent amount, agitation speed, initial As(III) concentration and temperature. Maximum sorption was occurred at pH 5.0 while the equilibrium was established in 8 h. Langmuir and Freundlich isotherm models were employed for fitting the experimental data. The maximum sorption capacity of CP was observed to be 36.311 姠g-1. The biosorption kinetics was speculated to follow pseudo-first-order kinetic model (R2 =0.998) with the sorption rate of 15.340ױ0-3 min-1 for the initial As(III) concentration of 500 姠L-1. The biosorbent material was characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). The activation energy (Ea) and heat of biosorption (?H) were calculated to be 17.780 and 30.724 kJ mol-1 respectively. Thermodynamic parameters were evaluated which revealed the spontaneous nature of biosorption on CP accompanied with the physical activated process. The break through characteristics of C. zeylanicum packed column was also investigated by small scale column tests (SSCT).