Novel porous calcium alginate beads were prepared via crosslinking of calcium followed by freeze drying for investigating the adsorption performance for methylene blue. These beads possessed reduced shrinkage, highly porous lamellar structure and high specific surface area, and exhibited enhanced adsorption capacity and much faster adsorption rate compared to the non-porous beads obtained with conventional oven drying method. Methylene blue adsorption capacity increased with increasing of initial concentration and pH, while decreased with increasing of temperature. The adsorption process fitted well with the pseudo-second-order kinetic model and the Langmuir isotherm. The maximum adsorption capacity was 961.5mg g-1 at 298.15 K. After eight successive adsorption-desorption cycles, the adsorption capacity had negligible decrease. Owing to the high adsorption capability, rapid adsorption rate, easy recovery and reusability, the freeze-dried beads imply a prospective, biodegradable and attractive adsorbent for removing contaminants from wastewater.