An electricity storage device has an electricity storage unit and a case that contains the electricity storage unit and a coolant for cooling the electricity storage unit. The case includes guide portions on an inner wall surface above the electricity storage unit, each of the guide portions having an oblique portion for, when gas is produced by the electricity storage unit, leading the gas to a predetermined position; and contact portions each of which protrudes in a direction of the electricity storage unit with respect to the oblique portions of the guide portions and is brought into contact with the coolant.