How to create a bootable USB stick on OS X

We would encourage Mac users to download Ubuntu Desktop Edition by burning a CD. But if you prefer to use a USB stick, please follow the instructions below.

Note: this procedure requires that you create an .img file from the .iso file you download.

提示: Drag and drop a file from Finder to Terminal to 'paste' the full path without risking typing errors.

  1. 1
  2. 2

    Open the Terminal (in /Applications/Utilities/ or query Terminal in Spotlight).

  3. 3

    Convert the .iso file to .img using the convert option of hdiutil (e.g.,hdiutil convert -format UDRW -o ~/path/to/target.img ~/path/to/ubuntu.iso)

    Note: OS X tends to put the .dmg ending on the output file automatically.

  4. 4

    Run diskutil list to get the current list of devices.

  5. 5

    Insert your flash media.

  6. 6

    Run diskutil list again and determine the device node assigned to your flash media (e.g. /dev/disk2).

  7. 7

    Run diskutil unmountDisk /dev/diskN (replace N with the disk number from the last command; in the previous example, N would be 2).

  8. 8

    Execute sudo dd if=/path/to/downloaded.img of=/dev/rdiskN bs=1m (replace /path/to/downloaded.img with the path where the image file is located; for example, ./ubuntu.imgor ./ubuntu.dmg).

    • Using /dev/rdisk instead of /dev/disk may be faster
    • If you see the error dd: Invalid number '1m', you are using GNU dd. Use the same command but replace bs=1m with bs=1M
    • If you see the error dd: /dev/diskN: Resource busy, make sure the disk is not in use. Start the 'Disk' and unmount (don't eject) the drive
  9. 9

    Run diskutil eject /dev/diskN and remove your flash media when the command completes.

  10. 10

    Restart your Mac and press alt/option key while the Mac is restarting to choose the USB stick.

如果你遇到了麻烦无法继续安装……提问 Ubuntu