a trpm8 related peptide fragment , comprising amino acid sequence as shown in seq id no : 1 - 18 is provided . furthermore , application of trpm8 protein , trpm8 related peptide fragment and their antibodies in preparing diagnostic reagent for chronic prostatitis / chronic pelvic pain syndromes is provided . by detecting level of trpm8 protein molecule , trpm8 related peptide fragment and their antibodies , the chronic prostatitis / chronic pelvic pain syndromes is effectively diagnosed , and the present invention is capable of effectively making a distinction between cp / cpps and other diseases of prostate . in addition , by intravenously or subcutaneously injecting 1 ˜ 30000 iu trpm8 protein or trpm8 related polypeptide fragments with or without combining nanoparticles for desensitization therapy , or monoclonal or polyclonal antibodies of the trpm8 protein or polypeptide fragments , the present invention is capable of curing or significantly relieve clinical symptoms of the chronic prostatitis / chronic pelvic pain syndromes and having an therapeutic effect .