The utility model discloses a suspension mechanism which includes a suspension support, a power device, a driving wheel, a driven wheel, a drive wheel, a suspension wheel, and a driving chain. The suspension support includes two supporting boards, a driving shaft, a driven shaft, and a suspension shaft. Each of the two supporting boards is provided with three through holes, and the driving shaft, the driven shaft, and the suspension shaft pass through the three through holes. The driving shaft is fixed on the driving shaft and is connected with the power device. The driven wheel is fixed on the driven shaft and is connected with the driving shaft via the driving chain. The drive wheel is fixed on the driven shaft. The suspension wheel is rotatingly connected with the suspension shaft. When the suspension mechanism works, the power device transmits power to the drive wheel, and then the suspension device is driven to move smoothly from left to right on a tubular bus. In addition, the suspension mechanism is sleeved on the tubular bus, so the danger of high-altitude fall is avoided, the personal injury and device damage are not easy to happen, and consequently the on-site high-altitude operation safety is guaranteed.