A block copolymer comprising a first block including a structural unit represented by Structural Formula 1 below and a second block including a structural unit represented by Structural Formula 4 below, wherein the first block satisfies one or more of Conditions 2 to 5 below, and the first block and the second block have different chemical structures from each other and an absolute value of a difference in surface energies of 10 mN/m or less, wherein the surface energies are obtained in accordance with method D defined in the description, Condition 2: a peak whose full width at half maximum ranges from 5 degrees to 70 degrees is observed in azimuthal angle ranges, in a diffraction pattern of a grazing-incidence wide-angle X-ray scattering (GIWAXS) spectrum, of -90 degrees to -70 degrees and 70 degrees to 90 degrees (the azimuthal angle is determined by setting an angle of out-of-plane diffraction pattern of the GIWAXS spectrum as 0 degrees), wherein a scattering vector ranges from 12 nm -1 to 16 nm -1, wherein the GIWAXS spectrum is obtained in accordance with method A defined in the description; Condition 3: a melting transition peak or an isotropic transition peak is produced in a range of -80 °C to 200 °C during DSC analysis, wherein the DSC analysis is performed in accordance with method B defined in the description; Condition 4: a peak whose full width at half maximum ranges from 0.2 to 0.9 nm -1 is observed when a scattering vector (q) ranges from 0.5 nm -1 to 10 nm -1 during X-ray diffraction analysis, wherein the XRD analysis is performed in accordance with method C defined in the description; Condition 5: the first block includes a side chain, wherein a number (n) of chain-forming atoms in the side chain and a scattering vector (q) during XRD analysis satisfy Mathematical Expression 2 below: 3 nm − 1 to 5 nm − 1 = nq / 2 × π wherein n represents a number of the chain-forming atoms included in the side chain, and q represents a smallest scattering vector (q) whose peak is detectable or a scattering vector (q) that is observed to have a peak with a largest peak area, during XRD analysis on the block copolymer, wherein the XRD analysis is performed in accordance with method C defined in the description, wherein R represents a hydrogen atom or a C 1 -C 4 alkyl group; X represents an oxygen atom, -C(=O)-O- or -O-C(=O)-; and Y represents a monovalent substituent that includes an aromatic structure having 6 to 18 carbon atoms to which a chain is connected, wherein the chain is a linear-chain alkyl group having 8 or more carbon atoms and which is directly linked to the aromatic group or is linked to the aromatic group via an oxygen atom, wherein X 2 represents a single bond; and each of R 1 to R 5 independently represents hydrogen, an alkyl group, a haloalkyl group or a halogen atom, wherein one or more halogen atoms are contained in the positions marked as R 1 to R 5. Condition 2: a peak whose full width at half maximum ranges from 5 degrees to 70 degrees is observed in azimuthal angle ranges, in a diffraction pattern of a grazing-incidence wide-angle X-ray scattering (GIWAXS) spectrum, of -90 degrees to -70 degrees and 70 degrees to 90 degrees (the azimuthal angle is determined by setting an angle of out-of-plane diffraction pattern of the GIWAXS spectrum as 0 degrees), wherein a scattering vector ranges from 12 nm -1 to 16 nm -1, wherein the GIWAXS spectrum is obtained in accordance with method A defined in the description; Condition 3: a melting transition peak or an isotropic transition peak is produced in a range of -80 °C to 200 °C during DSC analysis, wherein the DSC analysis is performed in accordance with method B defined in the description; Condition 4: a peak whose full width at half maximum ranges from 0.2 to 0.9 nm -1 is observed when a scattering vector (q) ranges from 0.5 nm -1 to 10 nm -1 during X-ray diffraction analysis, wherein the XRD analysis is performed in accordance with method C defined in the description; Condition 5: the first block includes a side chain, wherein a number (n) of