An oxyntomodulin analogue GLP-1R/GCGR dual target agonist polypeptide for use in preventing or treating biliary cirrhosis diseases or related hepatic fibrosis course; wherein the polypeptide comprises a parent peptide represented by the following amino acid sequence: wherein, R 1 = -NH 2; Xaa2 = D-Ser; Xaa10 = Lys or Tyr; Xaa13 = Lys or Tyr; Xaa16 = Ser, Aib or Lys; Xaa17 = Lys or Arg; Xaa18 = Arg or Ala; Xaa20 = His or Gin; Xaa21 =Asp; Xaa23 = Val; Xaa24 = Glu or Gin; Xaa27 = Met, Leu or Nle; Xaa28 = Asn or Arg; Xaa29 = Thr or is absent; Xaa30 = Gly or is absent; Xaa31 = Gly or is absent; Xaa32 = Pro or is absent; Xaa33 = Ser or is absent; Xaa34 = Ser or is absent; Xaa35 = Gly or is absent; Xaa36 = Ala or is absent; Xaa37 = Pro or is absent; Xaa38 = Pro or is absent; Xaa39 = Pro or is absent; Xaa40 = Ser or is absent; wherein at least one of Xaa10, Xaa16, Xaa17 or Xaa20 is Lys, the side chain of the at least one Lys or the Lys at position 12 of the sequence is attached to a lipophilic substituent in such a way that a carboxyl group of the lipophilic substituent forms an amide bond with an amino of a bridging group, the bridging group is attached to the parent peptide by means of a carboxyl group of the amino acid residue of the bridging group which forms an amide bond with a N-terminal residue of Lys of the parent peptide, the bridging group is Glu, Asp and/or m, wherein m is an integer of 2-10; the lipophilic substituent is an acyl group selected from CH 3 (CH 2) n CO- or HOOC(CH 2) n CO-, wherein n is an integer of 10-24; wherein when the position 10, 12, 16, 17, or 20 of the amino acid sequence is Lys, the lipophilic substituent attached to the side chain of the Lys is one of the following structures: Lys(PEG 2 -PEG 2 -CO(CH 2) 14 CH 3) Lys(PEG 2 -PEG 2 -γGlu-CO(CH 2) 14 CH 3) Lys(PEG 2 -PEG 2 -CO(CH 2) 14 CO 2 H) Lys(PEG 2 -PEG 2 -γGlu-CO(CH 2) 14 CO 2 H) Lys(PEG 2 -PEG 2 -CO(CH 2) 16 CO 2 H) Lys(PEG 2 -PEG 2 -γGlu-CO(CH 2) 16 CO 2 H) Lys(PEG 2 -PEG 2 -CO(CH 2) 16 CH 3) Lys(PEG 2 -PEG 2 -γGlu-CO(CH 2) 16 CH 3) wherein the polypeptide comprises a parent peptide represented by the following amino acid sequence: wherein, R 1 = -NH 2; Xaa2 = D-Ser; Xaa10 = Lys or Tyr; Xaa13 = Lys or Tyr; Xaa16 = Ser, Aib or Lys; Xaa17 = Lys or Arg; Xaa18 = Arg or Ala; Xaa20 = His or Gin; Xaa21 =Asp; Xaa23 = Val; Xaa24 = Glu or Gin; Xaa27 = Met, Leu or Nle; Xaa28 = Asn or Arg; Xaa29 = Thr or is absent; Xaa30 = Gly or is absent; Xaa31 = Gly or is absent; Xaa32 = Pro or is absent; Xaa33 = Ser or is absent; Xaa34 = Ser or is absent; Xaa35 = Gly or is absent; Xaa36 = Ala or is absent; Xaa37 = Pro or is absent; Xaa38 = Pro or is absent; Xaa39 = Pro or is absent; Xaa40 = Ser or is absent; wherein, R 1 = -NH 2; Xaa2 = D-Ser; Xaa10 = Lys or Tyr; Xaa13 = Lys or Tyr; Xaa16 = Ser, Aib or Lys; Xaa17 = Lys or Arg; Xaa18 = Arg or Ala; Xaa20 = His or Gin; Xaa21 =Asp; Xaa23 = Val; Xaa24 = Glu or Gin; Xaa27 = Met, Leu or Nle; Xaa28 = Asn or Arg; Xaa29 = Thr or is absent; Xaa30 = Gly or is absent; Xaa31 = Gly or is absent; Xaa32 = Pro or is absent; Xaa33 = Ser or is absent; Xaa34 = Ser or is absent; Xaa35 = Gly or is absent; Xaa36 = Ala or is absent; Xaa37 = Pro or is absent; Xaa38 = Pro or is absent; Xaa39 = Pro or is absent; Xaa40 = Ser or is absent; wherein at least one of Xaa10, Xaa16, Xaa17 or Xaa20 is Lys, the side chain of the at least one Lys or the Lys at position 12 of the sequence is attached to a lipophilic substituent in such a way that a carboxyl group of the lipophilic substituent forms an amide bond with an amino of a bridging group, the bridging group is attached to the parent peptide by means of a carboxyl group of the amino acid residue of the bridging group which forms an amide bond with a N-terminal residue of Lys of the parent peptide, the bridging group is Glu, Asp and/or m, wherein m is an integer of 2-10; the lipophilic substituent is an acyl group selected from CH 3 (CH 2) n CO- or HOOC(CH 2) n CO-, wherein n is an integer of 10-24; wherein when the position 10, 12, 16, 17, or 20 of the amino acid sequence is Lys, the lipophilic substituent attached to the side chain of the Lys is one of the following structures: Lys(PEG 2 -PEG 2 -CO(CH 2) 14 CH 3) Lys(PEG 2 -PEG 2 -γGlu-CO(CH 2) 14 CH 3) Lys(PEG 2 -PEG 2 -CO(CH 2) 14 CO 2 H) Lys(PEG 2 -PEG 2 -γGlu-CO(CH 2) 14 CO 2 H) Lys(PEG 2 -PEG 2 -CO(CH 2) 16 CO 2 H) Lys(PEG 2 -PEG 2 -γGlu-CO(CH 2) 16 CO 2 H) Lys(PEG 2 -PEG 2 -CO(CH 2) 16 CH 3) Lys(PEG 2 -PEG 2 -γGlu-CO(CH 2) 16 CH 3) Lys(PEG 2 -PEG 2 -CO(CH 2) 14 CH 3) Lys(PEG 2 -PEG 2 -γGlu-CO(CH 2) 14 CH 3) Lys(PEG 2 -PEG 2 -CO(CH 2) 14 CO 2 H) Lys(PEG 2 -PEG 2 -γGlu-CO(CH 2) 14 CO 2 H) Lys(PEG 2 -PEG 2 -CO(CH 2) 16 CO 2 H) Lys(PEG 2 -PEG 2 -γGlu-CO(CH 2) 16 CO 2 H) Lys(PEG 2 -PEG 2 -CO(CH 2) 16 CH 3) Lys(PEG 2 -PEG 2 -γGlu-CO(CH 2) 16 CH 3)