The recombinant strain Escherichia coli BL21∷pET30aHcUKPP was obtained by the method of prokaryotic vector construction after cloning of unknown functional peptide HcUKPP gene, and then tested its tolerance under different abiotic stresses. The results revealed that open reading frame(ORF) of the gene was 243 bp, the molecular weight of the recombinant HcUKPP was approximately 15 kD. In addition, the expression of HisHcUKPP fusion protein could be induced with different concentrations of isopropyl βD1thiogalactopyranoside (IPTG) for 4 h at 37 ℃. Furthermore, the growth of recombinant strain E.coli BL21∷pET30aHcUKPP have shown obvious advantages under treatment of different concentrations of NaCl (100-900 mmol/L), polyethylene glycol (2.5%-20%, PEG 6000) and methyl viologen (25-200 μmol/L). Especially under the condition of 500 mmol/L NaCl, 10% PEG 6000 and 75 μmol/L methyl viologen for 12 h, interestingly，recombinant E.coli BL21 showed significant advantages, their growth reached 1.81, 1.47 and 3.48 fold of control bacteria respectively. Overall, the HcUKPP gene of Halostachys caspica can significantly improve tolerance of recombinant E.coli BL21 under different abiotic stresses, which proved that the HcUKPP is a kind of newly discovered polypeptide in response to abiotic stress.