An anti-IL-6 receptor antibody comprising a heavy chain variable region of SEQ ID NO: 17 and a light chain variable region of SEQ ID NO: 18, in which: CDR1 of the heavy chain variable region consists of the amino acid sequence of SEQ ID NO: 1 in which Ser at position 1 has been substituted with Asp; CDR2 of the heavy chain variable region consists of the amino acid sequence of SEQ ID NO: 2 in which Thr at position 9 and Ser at position 16 have been substituted with Asn and Gly, respectively; CDR1 of the light chain variable region consists of the amino acid sequence of SEQ ID NO: 4 in which Arg at position 1 has been substituted with Gln; CDR2 of the light chain variable region consists of the amino acid sequence of SEQ ID NO: 5 in which Thr at position 2 and Arg at position 4 have been substituted with Gly and Glu, respectively; CDR3 of the light chain variable region consists of the amino acid sequence of SEQ ID NO: 6 in which Thr at position 5 has been substituted with Ser; FR1 of the heavy chain variable region consists of the amino acid sequence of SEQ ID NO: 7 in which Arg at position 13, Gln at position 16, Thr at position 23 and Thr at position 30 have been substituted with Lys, Glu, Ala and Ser, respectively; FR2 of the heavy chain variable region consists of the amino acid sequence of SEQ ID NO: 8 in which Arg at position 8 has been substituted with Glu; FR3 of the heavy chain variable region consists of the amino acid sequence of SEQ ID NO: 9 in which Met at position 4, Leu at position 5, Arg at position 16 and Val at position 27 have been substituted with Ile, Ser, Lys and Ala, respectively; FR4 of the heavy chain variable region consists of the amino acid sequence of SEQ ID NO: 10 in which Gln at position 3 and Ser at position 5 have been substituted with Glu and Thr, respectively; FR1 of the light chain variable region consists of the amino acid sequence of SEQ ID NO: 11 in which Arg at position 18 has been substituted with Ser; FR2 of the light chain variable region consists of the amino acid sequence of SEQ ID NO: 12 in which Lys at position 11 has been substituted with Glu; FR3 of the light chain variable region consists of the amino acid sequence of SEQ ID NO: 13 in which Gln at position 23, Pro at position 24 and Ile at position 27 have been substituted with Glu, Ala and Ala, respectively; and FR4 of the light chain variable region consists of the amino acid sequence of SEQ ID NO: 14 in which Lys at position 10 has been substituted with Glu. CDR1 of the heavy chain variable region consists of the amino acid sequence of SEQ ID NO: 1 in which Ser at position 1 has been substituted with Asp; CDR2 of the heavy chain variable region consists of the amino acid sequence of SEQ ID NO: 2 in which Thr at position 9 and Ser at position 16 have been substituted with Asn and Gly, respectively; CDR1 of the light chain variable region consists of the amino acid sequence of SEQ ID NO: 4 in which Arg at position 1 has been substituted with Gln; CDR2 of the light chain variable region consists of the amino acid sequence of SEQ ID NO: 5 in which Thr at position 2 and Arg at position 4 have been substituted with Gly and Glu, respectively; CDR3 of the light chain variable region consists of the amino acid sequence of SEQ ID NO: 6 in which Thr at position 5 has been substituted with Ser; FR1 of the heavy chain variable region consists of the amino acid sequence of SEQ ID NO: 7 in which Arg at position 13, Gln at position 16, Thr at position 23 and Thr at position 30 have been substituted with Lys, Glu, Ala and Ser, respectively; FR2 of the heavy chain variable region consists of the amino acid sequence of SEQ ID NO: 8 in which Arg at position 8 has been substituted with Glu; FR3 of the heavy chain variable region consists of the amino acid sequence of SEQ ID NO: 9 in which Met at position 4, Leu at position 5, Arg at position 16 and Val at position 27 have been substituted with Ile, Ser, Lys and Ala, respectively; FR4 of the heavy chain variable region consists of the amino acid sequence of SEQ ID NO: 10 in which Gln at position 3 and Ser at position 5 have been substituted with Glu and Thr, respectively; FR1 of the light chain variable region consists of the amino acid sequence of SEQ ID NO: 11 in which Arg at position 18 has been substituted with Ser; FR2 of the light chain variable region consists of the amino acid sequence of SEQ ID NO: 12 in which Lys at position 11 has been substituted with Glu; FR3 of the light chain variable region consists of the amino acid sequence of SEQ ID NO: 13 in which Gln at position 23, Pro at position 24 and Ile at position 27 have been substituted with Glu, Ala and Ala, respectively; and FR4 of the light chain variable region consists of the amino acid sequence of SEQ ID NO: 14 in which Lys at position 10 has been substituted with Glu.