A vehicle battery mounting structure having a service hole cover that closes a service hole the service hole cover includes a rear cover that covers a rear end side of the service hole in a vehicle longitudinal direction and a front cover that covers a front end side of the service hole in the vehicle longitudinal direction. That is, the service hole cover is split into the rear cover and the front cover in the vehicle longitudinal direction. The front cover is detachably attached to a floor upper reinforcement provided on a floor panel by bolts.