An energy storage apparatus includes an energy storage device and an adjacent member adjacent to the energy storage device, wherein the energy storage device includes a case body for accommodating an electrode assembly, the case body having a body part including an opening at least a first end of the body part in a first direction, and a lid for closing the opening, the body part has a thick-walled part formed at least one of the first end and a second end of the body part in the first direction and a thin-walled part thinner than the thick-walled part, the adjacent member has a pair of sealing parts disposed at an interval in the first direction, and each of the sealing parts is in contact with the thin-walled part.