An optical fiber holder for holding an optical fiber (100, 200, 300), comprising: a holder body part on which either a first optical fiber, a second optical fiber or a third optical fiber is mountable, the second optical fiber having a coated part with an outer diameter larger than that of a coated part of the first optical fiber; wherein the third optical fiber is configured by providing a jacket on an outer circumference of the first optical fiber or the second optical fiber; a lid body which is disposed to be openable and closable with respect to the holder body part; wherein an inner surface side of the lid body is provided with a pressing member at a position corresponding to a place where the optical fiber (100, 200) is mounted; wherein, the pressing member is urged in a closed direction of the lid body by two spring members disposed between the lid body and the pressing member; and a fiber posture correction block which is provided on the lid body on a side close to a terminal processing part of the first optical fiber and the second optical fiber, wherein the holder body part includes a first regulating part at an end part thereof on a terminal processing part side, and the first regulating part is configured to regulate movement of a first glass fiber exposed from the first optical fiber or a second glass fiber exposed from the second optical fiber, wherein the first regulating part comprises an upward protruding part provided so as to protrude upward and including a recessed part for projecting the first or second glass fiber exposed from the first or second optical fiber (100, 200) outward of the optical fiber holder, and a pair of wall parts provided on both sides of the recessed part; wherein the fiber posture correction block includes an attachment part, a front protruding part and a downward protruding part defining a contact part to be in contact with the second optical fiber at an end part thereof on the terminal processing part side; characterised in that the downward protruding part includes a recessed part extending in parallel with a longitudinal direction of the optical fiber (100, 200), and a pair of wall parts provided downward on both sides of the recessed part to accommodate the second optical fiber; and the recessed part of the contact part includes an inclined surface (46A1) configured to correct said third optical fiber to be downward along the inclined surface in a case where the third optical fiber is held to be fixed, wherein the inclined surface (46A1) is formed as an arc shape by the pair of wall parts on an end surface thereof and is inclined upward from a front of the downward protruding part toward a rear. a holder body part on which either a first optical fiber, a second optical fiber or a third optical fiber is mountable, the second optical fiber having a coated part with an outer diameter larger than that of a coated part of the first optical fiber; wherein the third optical fiber is configured by providing a jacket on an outer circumference of the first optical fiber or the second optical fiber; a lid body which is disposed to be openable and closable with respect to the holder body part; wherein an inner surface side of the lid body is provided with a pressing member at a position corresponding to a place where the optical fiber (100, 200) is mounted; wherein, the pressing member is urged in a closed direction of the lid body by two spring members disposed between the lid body and the pressing member; and a fiber posture correction block which is provided on the lid body on a side close to a terminal processing part of the first optical fiber and the second optical fiber, wherein the holder body part includes a first regulating part at an end part thereof on a terminal processing part side, and the first regulating part is configured to regulate movement of a first glass fiber exposed from the first optical fiber or a second glass fiber exposed from the second optical fiber, wherein the first regulating part comprises an upward protruding part provided so as to protrude upward and including a recessed part for projecting the first or second glass fiber exposed from the first or second optical fiber (100, 200) outward of the optical fiber holder, and a pair of wall parts provided on both sides of the recessed part; wherein the fiber posture correction block includes an attachment part, a front protruding part and a downward protruding part defining a contact part to be in contact with the second optical fiber at an end part thereof on the terminal processing part side; characterised in that the downward protruding part includes a recessed part extending in parallel with a longitudinal direction of the optical fiber (100, 200), and a pair of wall parts provided downward on both sides of the recessed part to accommodate the second optical fiber; and the recessed part of the contact part includes an inclined surface (46A1) configured to correct said third optical fiber to be downward along the inclined surface in a case where the third optical fiber is held to be fixed, wherein the inclined surface (46A1) is formed as an arc shape by the pair of wall parts on an end surface thereof and is inclined upward from a front of the downward protruding part toward a rear.