macOS High Sierra
Delete a recording
You can delete a recording from your Mac or from iCloud. Deleting a recording from iCloud removes it from all of your devices that are set up with iCloud and have iCloud Drive turned on.
Choose File > Open File, then find the recording you want to delete.
If the recording is saved in iCloud Drive, select QuickTime Player in the iCloud section of the Finder sidebar to see the recording. For more information about working with files in iCloud, see Store your desktop and documents in iCloud Drive.
Drag the recording to the Trash icon in the Dock.
If you’re deleting from iCloud, click Delete. The recording is removed from all of your devices set up with iCloud Drive.
The recording isn’t deleted from your Mac until you empty the Trash.