An instrument device comprising an indicator panel, an instrument main part which is disposed at a rear face side of the indicator panel, an indicator needle which is provided so as to rotate and give an indication in accordance with an operation of the instrument main part along a front face side of the indicator panel, a transparent light-guiding member which is disposed on the front face side of the indicator panel and which can be seen through, and a light source which emits a light beam into the light-guiding member, wherein the light-guiding member is provided with a light-guiding portion (61, 61 a) which is disposed at an outer circumferential portion of the light-guiding member, and which reflects and guides the light beam from the light source inwardly to the light-guiding member with directivity, characterized in that the instrument further comprises a light reflective portion (63, 63c) which comprises a plurality of concavities and convexities and which is formed at a rear face of the light-guiding member, wherein the light guiding portion (61,61 a) is adapted to reflect and guide the light beam from the light source towards a center of rotation of the indicator needle and wherein the light-guiding portion (61, 61a) is adapted to reflect and guide the light beam from the light source with directivity such that the light beam from the light source reaches a partial region of the light reflective portion (63, 63a), the partial region being a strip-shaped or linear region, the strip-shaped or linear region reached by the light beam from the light source reflects and guides the light beam toward a viewer so that an area of the light reflective portion (63, 63a) is observed to shine like a strip or a line when the instrument device is viewed from a front by the viewer, wherein a scale (55a, 62) to be indicated by the indicator needle is formed on the light-guiding member or in the indicator panel such that the scale (55a, 62) is along a line which interconnects the light-guiding portion (61, 61 a) and the center of rotation of the indicator needle, and when the instrument device is viewed from the front, the area observed to shine like a strip or a line includes a portion extending from the scale (55a, 62) toward the center of rotation. the light-guiding member is provided with a light-guiding portion (61, 61 a) which is disposed at an outer circumferential portion of the light-guiding member, and which reflects and guides the light beam from the light source inwardly to the light-guiding member with directivity, a light reflective portion (63, 63c) which comprises a plurality of concavities and convexities and which is formed at a rear face of the light-guiding member, wherein the light guiding portion (61,61 a) is adapted to reflect and guide the light beam from the light source towards a center of rotation of the indicator needle and the strip-shaped or linear region reached by the light beam from the light source reflects and guides the light beam toward a viewer so that an area of the light reflective portion (63, 63a) is observed to shine like a strip or a line when the instrument device is viewed from a front by the viewer, wherein a scale (55a, 62) to be indicated by the indicator needle is formed on the light-guiding member or in the indicator panel such that the scale (55a, 62) is along a line which interconnects the light-guiding portion (61, 61 a) and the center of rotation of the indicator needle, and when the instrument device is viewed from the front, the area observed to shine like a strip or a line includes a portion extending from the scale (55a, 62) toward the center of rotation.