Provided are five kinds of scorpion active peptides having the amino acid sequences as shown in SEQ ID NO: 1, SEQ ID NO: 2, SEQ ID NO: 3, SEQ ID NO: 13 and SEQ ID NO: 14, respectively. Also provided are the genes encoding the active peptides, preparation methods of the active peptides, and applications of the active peptides in the preparation of a medicament for treating or preventing diseases associated with potassium channel KV1.3.