Foundamental Courses of Aquatic Products Science. Characteristics of enzymes extracted from abalone (Haliotis discus hannai Ino) intestine and purification of the alginate lyase. The enzymes extracted from abalone (Haliotis discus hannai Ino) intestine were studied for finding the alginate and cellulose degradation enzymes. The enzymes were separated and partially purified from abalone intestine by using ammonium sulfate precipitations, and successive fractionation on DEAE-52, SephadexG-200 column chromatography. The results showed that their were four types of enzyme separated, which were alginate lyase Ⅰ, lyase Ⅱ, cellulase and agarase. The characteristics of alginate lyase Ⅰ,lyase Ⅱ and cellulase related with pH, temperature and ions were also determined and the results indicated that alginate lyase Ⅰ has the maximum activity at pH 8.6 and 35 ℃. Alginate lyase Ⅱ has maximum activity at pH 7.2 and 35 ℃. Cellulase has maximum activity at pH 5.0 and 40 ℃. The alginate lyaseⅠ and lyase Ⅱ were not stable at high temperature. The crude enzymes exstracted could be obviously activated by Mn2+, Al3+,Ca2+,Cu2+ and inhibited by Na+. SDS-PAGE was used for estimating the molecular weights of enzymes and the findings showed that the molecular weights of alginate lyase Ⅰ, Ⅱ were to be 35.2 ku, 67 ku. The findings indicated that there were two types of alginate enzyme could be obtained from abalone(Haliotis discus hannai Ino) intestine and the studies established the purification steps and theoretical base for further work, reconstruction, production and application of three enzymes. Further work should be carried out on the N end and sequences of the enzymes. 12 Refs.In Chinese. Key words: Haliotis discus hannai Ino; alginate lyase; cellulose; purification KANG Ping(Department of Food Engineering, Dalian Fisheries University, Dalian116023, China) , WANG Qiu-kuan, SONG Lin-lin, XU Ling//J Fish China,2007,31(1).15-22