Disclosed are a superoxide dismutase gene and an encoded protein thereof. The DNA sequence of the superoxide dismutase gene is as shown in SEQ ID NO. 1, and the amino acid sequence of the protein encoded by the gene is as shown in SEQ ID NO. 2. The superoxide dismutase has both a good heat resistance and a good freeze-thaw resistance, and can be applied to the fields of cosmetics, food, medicine, environmental protection and the like.