To provide an ice heat storage tank comprising a cooling coil unit where bridging and water seal hardly occur.

In this ice heat storage tank 10 wherein the cooling coil unit 20 formed by layering a cooling coil 21 where a plurality of refrigerant pipe conduits 22 arranged at specific intervals are reciprocated and communicated on the same plane, in multiple layers at specific intervals, is mounted inside, and a refrigerant circulated in the cooling coil unit 20 absorbs the heat from the heat storage medium C to cool the same, the cooling coil unit 20 comprises a part where the refrigerant pipe conduits 22 adjacent to each other in the stacking direction are intersected with each other.