The invention provides a tape reel supporting device, a component placement machine, and a tape reel supporting method. A tape reel supporting device includes a plurality of shaft members and a plurality of roller members. The plurality of shaft members extend to be parallel to each other in a horizontal direction. The plurality of roller members are provided to be externally fitted into each of the plurality of shaft members, and each of two inclined surfaces inclined to an axis of each shaft member abuts on an outer peripheral edge of each of a pair of disk members. The two inclined surfacesprovided on each of the plurality of roller members are inclined in directions opposite to each other in a direction along an axis of each shaft member on which the roller member is provided.