A fixed type constant velocity universal joint, comprising: an outer joint member having an inner spherical surface in which a plurality of track grooves extending in an axial direction are formed; an inner joint member having an outer spherical surface in which a plurality of track grooves extending in the axial direction while paired with the track grooves of the outer joint member are formed; a plurality of balls interposed between the track grooves of the outer joint member and the track grooves of the inner joint member, for transmitting a torque; and a cage interposed between the inner spherical surface of the outer joint member and the outer spherical surface of the inner joint member, for holding the balls, the outer joint member and the inner joint member each having a center curvature (0 1, 0 2) of the track grooves (11, 14) being offset from each other in a direction opposite to the axial direction by an equal distance (f) with respect to a joint center, and a pitch circle diameter gap (m) in a ball track formed between the track grooves of the outer joint member and the track grooves of the inner joint member is set, a number of the balls are eight, and a nip angle (γ8) of each of the balls located between the track grooves of the outer joint member and the track grooves of the inner joint member with respect to the track grooves (11, 14) is set to 8.5 to 12.5°; a contact angle (α8) of each of the balls with respect to the track grooves (11, 14) is set to 30 to 38°; wherein the PCD gap (m) is set larger than 50 μm and to equal to or smaller than 77 μm characterized in that a spherical surface gap formed between the outer spherical surface of the inner joint member and an inner spherical surface of the cage is set equal to or larger than 108 μm and to smaller than or equal to 132 μm; a spherical surface gap formed between an outer spherical surface of the cage and the inner spherical surface of the outer joint member is set equal to or larger than 117 μm and to smaller than or equal to 143 μm; and wherein the spherical surface gaps (n1, n2) are larger than the movable amount of the cage in the axial direction determined based on the PCD gap (m). an outer joint member having an inner spherical surface in which a plurality of track grooves extending in an axial direction are formed; an inner joint member having an outer spherical surface in which a plurality of track grooves extending in the axial direction while paired with the track grooves of the outer joint member are formed; a plurality of balls interposed between the track grooves of the outer joint member and the track grooves of the inner joint member, for transmitting a torque; and a cage interposed between the inner spherical surface of the outer joint member and the outer spherical surface of the inner joint member, for holding the balls, the outer joint member and the inner joint member each having a center curvature (0 1, 0 2) of the track grooves (11, 14) being offset from each other in a direction opposite to the axial direction by an equal distance (f) with respect to a joint center, and a pitch circle diameter gap (m) in a ball track formed between the track grooves of the outer joint member and the track grooves of the inner joint member is set, a number of the balls are eight, and a nip angle (γ8) of each of the balls located between the track grooves of the outer joint member and the track grooves of the inner joint member with respect to the track grooves (11, 14) is set to 8.5 to 12.5°; a contact angle (α8) of each of the balls with respect to the track grooves (11, 14) is set to 30 to 38°; wherein the PCD gap (m) is set larger than 50 μm and to equal to or smaller than 77 μm characterized in that a spherical surface gap formed between the outer spherical surface of the inner joint member and an inner spherical surface of the cage is set equal to or larger than 108 μm and to smaller than or equal to 132 μm; a spherical surface gap formed between an outer spherical surface of the cage and the inner spherical surface of the outer joint member is set equal to or larger than 117 μm and to smaller than or equal to 143 μm; and wherein the spherical surface gaps (n1, n2) are larger than the movable amount of the cage in the axial direction determined based on the PCD gap (m).