The present invention belongs to the field of biological medicine, and provides a polypeptide having an analgesic activity, a pharmaceutically acceptable salt thereof and uses thereof. Said polypeptide has a pair of disulfide bridges formed between the two cysteines of the amino acid sequence Gly-Cys-Ser-Ser-Thr-Pro-Pro-Cys. Said polypeptide inhibits physical and chemical stimuli, pathological and neurological pains, while prolongating the duration of heat tolerance in mice. Adverse reactions in mice, such as voluntary movement, excitability, and the like are lower than the normal values.