A battery storage device of a vehicle comprising: a battery case that has an inserting/removing port for inserting and removing a battery (62A or 62B); a case side connection terminal that protrudes upward below the battery case and is connected to a terminal portion of the battery (62A or 62B) inserted into the battery case; and a lid member that is capable of opening and closing an upper part of the battery case, wherein the battery storage device of a vehicle further comprises a lock mechanism that is capable of fixing the battery (62A or 62B) stored in the battery case to the battery case below the lid member, and an operation member that is capable of operating the lock mechanism, and wherein the operation member is constituted such that at least a part thereof overlaps the inserting/removing port on an upper side in a view in an insertion direction of the battery (62A or 62B) in a state at a lock operation position, characterized in that the battery storage device further comprises a terminal displacement mechanism that causes the case side connection terminal to be displaced between a connection position protruding upward from a bottom portion of the battery case and a retreat position retreated downward from the connection position, wherein the operation member is also capable of operating the terminal displacement mechanism, and wherein the operation member is constituted such that at least a part thereof overlaps the inserting/removing port on the upper side in a view in the insertion direction of the battery (62A or 62B) in a state at a connection operation position where the case side connection terminal is displaced to the connection position. a battery case that has an inserting/removing port for inserting and removing a battery (62A or 62B); a case side connection terminal that protrudes upward below the battery case and is connected to a terminal portion of the battery (62A or 62B) inserted into the battery case; and a lid member that is capable of opening and closing an upper part of the battery case, wherein the battery storage device of a vehicle further comprises a lock mechanism that is capable of fixing the battery (62A or 62B) stored in the battery case to the battery case below the lid member, and an operation member that is capable of operating the lock mechanism, and a lock mechanism that is capable of fixing the battery (62A or 62B) stored in the battery case to the battery case below the lid member, and an operation member that is capable of operating the lock mechanism, and wherein the operation member is constituted such that at least a part thereof overlaps the inserting/removing port on an upper side in a view in an insertion direction of the battery (62A or 62B) in a state at a lock operation position, characterized in that the battery storage device further comprises a terminal displacement mechanism that causes the case side connection terminal to be displaced between a connection position protruding upward from a bottom portion of the battery case and a retreat position retreated downward from the connection position, wherein the operation member is also capable of operating the terminal displacement mechanism, and wherein the operation member is constituted such that at least a part thereof overlaps the inserting/removing port on the upper side in a view in the insertion direction of the battery (62A or 62B) in a state at a connection operation position where the case side connection terminal is displaced to the connection position.