Abstract: A mount bracket includes a fixation frame provided with a clamp groove running through both ends and configured to be clamped to a window frame or a windowsill through two opposite sidewalls. At least one of the sidewalls is provided with a fixation hole for a fastener to pass through, and the fixation frame is configured to be locked to the window frame or the windowsill through at least the fastener. The mount bracket further includes a support frame rotatably connected to the fixation frame and configured to abut against a support surface in a mounting environment, and a machine body shelf connected to the support frame and configured to receive an air conditioner.