An imaging device comprising: an imaging unit; and a bracket capable of mounting the-imaging unit in a mounting direction, wherein the imaging unit includes a plurality of supported parts supported by the bracket, the bracket includes a plurality of support structures for supporting the plurality of supported parts, and the support structure includes: a receiving port that opens toward a rear in the mounting direction to receive the supported part in the mounting direction; and a support for supporting the supported part on the forward side in the mounting direction of the receiving port from a support direction that intersects the mounting direction, wherein the plurality of support structures includes at least one first support structure, and the first support structure is configured such that the support includes: an engagement recess provided in a recessed shape in the support direction to engage the supported part; and a guide part extending from a rear side to a front side of the receiving port in the mounting direction, wherein the support direction is an up-down direction, the engagement recess supports the supported part from below, and the guide part supports the supported part from above, characterized in that the guide part has a rear end portion in the mounting direction defined as a fixed end, a front end portion in the mounting direction defined as a free end, and uses the front end portion to bias the supported part toward the engagement recess. an imaging unit; and a bracket capable of mounting the-imaging unit in a mounting direction, wherein the imaging unit includes a plurality of supported parts supported by the bracket, the bracket includes a plurality of support structures for supporting the plurality of supported parts, and the support structure includes: a receiving port that opens toward a rear in the mounting direction to receive the supported part in the mounting direction; and a support for supporting the supported part on the forward side in the mounting direction of the receiving port from a support direction that intersects the mounting direction, wherein the plurality of support structures includes at least one first support structure, and the first support structure is configured such that the support includes: an engagement recess provided in a recessed shape in the support direction to engage the supported part; and a guide part extending from a rear side to a front side of the receiving port in the mounting direction, wherein the support direction is an up-down direction, the engagement recess supports the supported part from below, and the guide part supports the supported part from above, characterized in that a bracket capable of mounting the-imaging unit in a mounting direction, wherein the imaging unit includes a plurality of supported parts supported by the bracket, the bracket includes a plurality of support structures for supporting the plurality of supported parts, and the support structure includes: a receiving port that opens toward a rear in the mounting direction to receive the supported part in the mounting direction; and a support for supporting the supported part on the forward side in the mounting direction of the receiving port from a support direction that intersects the mounting direction, wherein the plurality of support structures includes at least one first support structure, and the first support structure is configured such that the support includes: an engagement recess provided in a recessed shape in the support direction to engage the supported part; and a guide part extending from a rear side to a front side of the receiving port in the mounting direction, wherein the support direction is an up-down direction, the engagement recess supports the supported part from below, and the guide part supports the supported part from above, characterized in that a receiving port that opens toward a rear in the mounting direction to receive the supported part in the mounting direction; and a support for supporting the supported part on the forward side in the mounting direction of the receiving port from a support direction that intersects the mounting direction, wherein the plurality of support structures includes at least one first support structure, and the first support structure is configured such that the support includes: an engagement recess provided in a recessed shape in the support direction to engage the supported part; and a guide part extending from a rear side to a front side of the receiving port in the mounting direction, wherein the support direction is an up-down direction, the engagement recess supports the supported part from below, and the guide part supports the supported part from above, characterized in that the guide part has a rear end portion in the mounting direction defined as a fixed end, a front end portion in the mounting direction defined as a free end, and uses the front end portion to bias the supported part toward the engagement recess.