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 (P1) protruding upward from a bottom portion of the battery case and a retreat position (P2) retreated downward from the connection position (P1), 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 (P1). 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 (P1) protruding upward from a bottom portion of the battery case and a retreat position (P2) retreated downward from the connection position (P1), 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 (P1). <EOS>