A polyimide-based block copolymer comprising a first repeating unit represented by Chemical Formula 1, and a second repeating unit represented by Chemical Formula 2: wherein, in Chemical Formulae 1 and 2, L 1 and L 2 are the same as or different from each other in each repeating unit, and each is independently a single bond, -O-, -S-, -C(=O)-, -CH -, -S(=O) 2 -, -Si(CH 3) 2 -, - (CH 2) p - (wherein 1≤p≤10), -(CF 2) q - (wherein 1≤q≤10), -C(CH 3) 2 -, -C(CF 3) 2 -, -C(=O)NH-, or a C6 to C30 divalent aromatic organic group; R 1 and R 2 are independently -F, -Cl, -Br, -I, -CF 3, -CCl 3, -CBr 3, -Cl 3, -NO 2, -CN, - COCH 3, -CO 2 C 2 H 5, a silyl group containing three C1 to C10 aliphatic organic groups, a C1 to C10 aliphatic organic group, or a C6 to C20 aromatic organic group; n1 and n2 are independently 0 to 3; Ar 1 and Ar 2 are the same as or different from each other in each repeating unit, and each is independently a C6 to C30 divalent aromatic organic group, wherein Ar 2 comprises a C6 to C30 divalent aromatic organic group substituted with an acetate group (CH 3 COO-) or a hydroxyl group (HO-), and the divalent aromatic organic group exists alone, or two or more aromatic organic groups are bonded to each other to form a condensed ring, or two or more aromatic organic groups are linked by a single bond, -O-, -S-, -C(=O)-, -CH -, -S(=O) 2 -, -Si(CH 3) 2 -, -(CH 2) p - (wherein 1≤p≤10), -(CF 2) q - (wherein 1≤q≤10), -C(CH 3) 2 -, - C(CF 3) 2 -, or -C(=O)NH-; E 1 to E 4 are independently a single bond, -NH-, or -C(=O)-; and each Z 1 is the same as or different from each other in each repeating unit, and each is at least one selected from the group represented by Chemical Formula Z1: a first repeating unit represented by Chemical Formula 1, and a second repeating unit represented by Chemical Formula 2: wherein, in Chemical Formulae 1 and 2, L 1 and L 2 are the same as or different from each other in each repeating unit, and each is independently a single bond, -O-, -S-, -C(=O)-, -CH -, -S(=O) 2 -, -Si(CH 3) 2 -, - (CH 2) p - (wherein 1≤p≤10), -(CF 2) q - (wherein 1≤q≤10), -C(CH 3) 2 -, -C(CF 3) 2 -, -C(=O)NH-, or a C6 to C30 divalent aromatic organic group; R 1 and R 2 are independently -F, -Cl, -Br, -I, -CF 3, -CCl 3, -CBr 3, -Cl 3, -NO 2, -CN, - COCH 3, -CO 2 C 2 H 5, a silyl group containing three C1 to C10 aliphatic organic groups, a C1 to C10 aliphatic organic group, or a C6 to C20 aromatic organic group; n1 and n2 are independently 0 to 3; Ar 1 and Ar 2 are the same as or different from each other in each repeating unit, and each is independently a C6 to C30 divalent aromatic organic group, wherein Ar 2 comprises a C6 to C30 divalent aromatic organic group substituted with an acetate group (CH 3 COO-) or a hydroxyl group (HO-), and the divalent aromatic organic group exists alone, or two or more aromatic organic groups are bonded to each other to form a condensed ring, or two or more aromatic organic groups are linked by a single bond, -O-, -S-, -C(=O)-, -CH -, -S(=O) 2 -, -Si(CH 3) 2 -, -(CH 2) p - (wherein 1≤p≤10), -(CF 2) q - (wherein 1≤q≤10), -C(CH 3) 2 -, - C(CF 3) 2 -, or -C(=O)NH-; E 1 to E 4 are independently a single bond, -NH-, or -C(=O)-; and each Z 1 is the same as or different from each other in each repeating unit, and each is at least one selected from the group represented by Chemical Formula Z1: L 1 and L 2 are the same as or different from each other in each repeating unit, and each is independently a single bond, -O-, -S-, -C(=O)-, -CH -, -S(=O) 2 -, -Si(CH 3) 2 -, - (CH 2) p - (wherein 1≤p≤10), -(CF 2) q - (wherein 1≤q≤10), -C(CH 3) 2 -, -C(CF 3) 2 -, -C(=O)NH-, or a C6 to C30 divalent aromatic organic group; R 1 and R 2 are independently -F, -Cl, -Br, -I, -CF 3, -CCl 3, -CBr 3, -Cl 3, -NO 2, -CN, - COCH 3, -CO 2 C 2 H 5, a silyl group containing three C1 to C10 aliphatic organic groups, a C1 to C10 aliphatic organic group, or a C6 to C20 aromatic organic group; n1 and n2 are independently 0 to 3; Ar 1 and Ar 2 are the same as or different from each other in each repeating unit, and each is independently a C6 to C30 divalent aromatic organic group, wherein Ar 2 comprises a C6 to C30 divalent aromatic organic group substituted with an acetate group (CH 3 COO-) or a hydroxyl group (HO-), and the divalent aromatic organic group exists alone, or two or more aromatic organic groups are bonded to each other to form a condensed ring, or two or more aromatic organic groups are linked by a single bond, -O-, -S-, -C(=O)-, -CH -, -S(=O) 2 -, -Si(CH 3) 2 -, -(CH 2) p - (wherein 1≤p≤10), -(CF 2) q - (wherein 1≤q≤10), -C(CH 3) 2 -, - C(CF 3) 2 -, or -C(=O)NH-; E 1 to E 4 are independently a single bond, -NH-, or -C(=O)-; and each Z 1 is the same as or different from each other in each repeating unit, and each is at least one selected from the group represented by Chemical Formula Z1: