By oxidized to oxycellulose of bamboo with sodium periodate-formaldehyde method, a fine carrier for immobilized enzyme was prepared. The papain was immobilized by the carrier in this paper, and we investigated the factors for immobilized papain such as immobilization condition, its microenvironment, stability and so on. The results show that the modified bamboo oxycellulose was a fine carrier for immobilized papain when given 15mg/ml enzyme at 4℃and pH7.5 to immobilize 24h. Under the conditions of 50℃ and pH7.5, it had the best catalytic activity, the best one could be 805.5U/g .What's more, it is better than free enzyme for its thermal stability and alkali resistence, and it could remain 79.3% after 6 times repeated.