The purpose of the present invention is to provide a countermeasure for ink spills. Provided is an ink tank unit including: an ink tank (9) that is capable of storing ink; an ink injecting portion (101) disposed in a case (61) of the ink tank (9) and having an opening (125) through which the ink can be injected into the ink tank (9); and a second case (7) which, with respect to a fifth wall (75) of the case (61) in which the ink injection part (101) is provided, covers at least a portion thereof in the periphery of the ink injection part (101). A recess portion (121) and a side wall (145) that can guide the ink into the recess portion (121) are disposed in either the abovementioned peripheral portion of the fifth wall (75) and/or a portion of the second case (7) facing the abovementioned peripheral portion.
