A fluid ejection device ejecting a fluid, the fluid ejection device includes: a fluid ejection unit, a main chassis case, a fluid-containing pack, and a container case. The fluid ejection unit ejects a fluid onto an ejection target. The main chassis case houses the fluid ejection unit. The fluid-containing pack contains a fluid for ejection. The container case houses the fluid-containing pack. The container case is pivotably attached to the main chassis case and openable by rotation about a rotation shaft.