There is provided a magnetic recording/reproduction device which can appropriately supply lubricant to a metal-thin-film magnetic tape (1) containing no binder in a recording/reproduction surface even when the magnetic recording/reproduction device needs to be continuously performing recording/reproduction by using the magnetic tape (1) for a long time. The magnetic recording/reproduction device includes a lubricant supplier (10) which can supply lubricant to the magnetic tape (1) while the magnetic head (2) performing recording/reproduction on the magnetic tape (1). With this configuration, the lubricant supplier (10) can appropriately supply lubricant during recording/reproduction even to the magnetic tape (1) used in a magnetic recording/reproduction device that needs to keep continuously operating for a long time.