The invention relates to an ice bag capable of applying in preserving biological product repeatedly and a method for preparing the ice bag. The ice bag adopts a sealed plastic bag, mixed solution proportioned by super absorbent resin 1 to 6g per 100ml water is sealed in the bag, and the bag is frozen with the temperature of 10 to 20DEG C below zero for more than 12h. The super absorbent resin comprises one of polyacrylic ester type, polyvinyl alcohol, ethylene-vinlacetate copolymer, polyurethanes, polyethylene oxide, starch grafting copolymer, and composite water absorbing materials mixed with rubber, or combination of any two above materials. The preparation comprises the following steps: firstly, placing water and super absorbent resin into a sealed plastic bag simultaneously, adding super absorbent resin 1 to 6g into each 100ml water, secondly, dipping the super absorbent resin into water for 10 to 30min to form aquagel, thirdly, placing the plastic bag flatly or confirming the shape according to demands before freezing, fourthly, placing the plastic bag into a refrigerating room, an ice chest or an ice box with the temperature of 10 to 20DEG C below zero, and freezing for more than 12h. The ice bag has simple manufacture and prominent effect.