Abstract: A battery mounting structure includes a locking device 23 that fastens and releases a battery 13 mounted on a mounting part 16, and an auxiliary removal lever 24 that presses the battery 13 in a released state from the mounting part 16 in a removal direction. The locking device 23 has a cylindrical locking barrel 27. The auxiliary removal lever 24 has a pushing member 32 that presses the battery 13 in the removal direction and is pivotally supported by the locking barrel 27 so as to be fit onto the locking barrel 27.