Extracellular agarase of Bacillus cereus ASK202 was purified 32-fold, giving a single band on PAGE with activity staining. The M-r of purified agarase was determined as 90 kDa by SDS-PAGE. The N-terminal amino acid was sequenced and the sequence did not show homology to any other known agarases. The optimum pH and temperature were 7.0 and 40 degrees C, respectively. This enzyme was found to be a beta-agarase which catalyzed the hydrolysis of the beta-1,4 linkage of agarose to yield neoagarohexaose, neoagarotetraose and neoagarobiose.