An amphiphilic block copolymer, wherein the amphiphilic block copolymer contains hydrophilic chain segment, hydrophobic chain segment and a linker used to connect the hydrophilic chain segment and the hydrophobic chain segment; the structure of the linker can be C 1 -C 30 small molecular fragment; the C 1 -C 30 small molecular fragment can be substituted by one or more aromatic rings; and the structure of the linker is selected from any one of the following structures: wherein T 1 is single bond or p is 0 or 1, q is 1, 2 or 3, X 1 is -O-, -S- or -NH-; T 2 is single bond or r is 0, 1, 2, 3, 4 or 5; T 3 is single bond or Ar is aromatic ring, and the aromatic rings can be C 6 -C 20 aryl, C 6 -C 20 aryl substituted by R a, C 2 -C 20 heteroaryl, or C 2 -C 20 heteroaryl substituted by R b; R a and R b are each independently selected from C 1 -C 6 alkyl, C 1 -C 6 alkoxy, C 4 -C 6 cycloalkyl, halide, hydroxyl or nitro group; the number of R a can be one or more; when the number of R a is more than one, R a can be the same or different; the number of R b can be one or more; when the number of R b is more than one, R b can be the same or different; the heteroatom in the C 2 -C 20 heteroaryl or R b substituted C 2 -C 20 heteroaryl can be O, S or N; the number of the heteroatom can be one or more; when the number of the heteroatom is more than one, the heteroatoms can be the same or different; the hydrophilic chain segment can be polyethylene glycol chain segment or mono-protected polyethylene glycol chain segment with number-average molecular weight ranging from 400 to 20000; the hydrophobic chain segment can be one chain segment selected from the group consisting of polylactide chain segment, mono-protected polylactide chain segment, polyglycolide chain segment, mono-protected polyglycolide chain segment, poly (lactide-co-glycolide) chain segment, mono-protected poly (lactide-co-glycolide) chain segment, polycaprolactone chain segment, mono-protected polycaprolactone chain segment, polycarbonate chain segment, mono-protected polycarbonate chain segment, polydioxanone chain segment and mono-protected polydioxanone chain segment, with the number-average molecular weight ranging from 400 to 20000, wherein the number-average molecular weight was calculated based on H-NMR; or the amphiphilic block copolymer can be selected from any one of the group consisting of: wherein n=8-455; m=3-160. T 2 is single bond or r is 0, 1, 2, 3, 4 or 5; T 3 is single bond or Ar is aromatic ring, and the aromatic rings can be C 6 -C 20 aryl, C 6 -C 20 aryl substituted by R a, C 2 -C 20 heteroaryl, or C 2 -C 20 heteroaryl substituted by R b; R a and R b are each independently selected from C 1 -C 6 alkyl, C 1 -C 6 alkoxy, C 4 -C 6 cycloalkyl, halide, hydroxyl or nitro group; the number of R a can be one or more; when the number of R a is more than one, R a can be the same or different; the number of R b can be one or more; when the number of R b is more than one, R b can be the same or different; the heteroatom in the C 2 -C 20 heteroaryl or R b substituted C 2 -C 20 heteroaryl can be O, S or N; the number of the heteroatom can be one or more; when the number of the heteroatom is more than one, the heteroatoms can be the same or different; the hydrophilic chain segment can be polyethylene glycol chain segment or mono-protected polyethylene glycol chain segment with number-average molecular weight ranging from 400 to 20000; the hydrophobic chain segment can be one chain segment selected from the group consisting of polylactide chain segment, mono-protected polylactide chain segment, polyglycolide chain segment, mono-protected polyglycolide chain segment, poly (lactide-co-glycolide) chain segment, mono-protected poly (lactide-co-glycolide) chain segment, polycaprolactone chain segment, mono-protected polycaprolactone chain segment, polycarbonate chain segment, mono-protected polycarbonate chain segment, polydioxanone chain segment and mono-protected polydioxanone chain segment, with the number-average molecular weight ranging from 400 to 20000, wherein the number-average molecular weight was calculated based on H-NMR; or the amphiphilic block copolymer can be selected from any one of the group consisting of: wherein n=8-455; m=3-160.