An objective of the present invention is to provide an antifreeze protein which is capable of being efficiently produced on an industrial level at low cost and which is safe and has an excellent antifreezing activity for use on a practical level. Also, an objective of the present invention is to provide a polypeptide that corresponds to the active part of the antifreeze protein; a composition, a food, a biological sample protectant and a cosmetic containing the antifreeze protein or the polypeptide; and an antibody that specifically reacts with the antifreeze protein or the polypeptide. The antifreeze protein according to the present invention is characterized in being derived from a plant and having a specific amino acid sequence or being a plant seed protein.