The utility model discloses a suspension device of a tubular bus pre-arching machine. The tubular bus suspension device comprises a first suspension mechanism, a second suspension mechanism and a suspension box body, wherein the first suspension mechanism and the second suspension mechanism are respectively fixed on two ends of the suspension box body, and the first suspension mechanism and the second suspension mechanism respectively comprise a suspension bracket, a power device, a drive wheel, a driven wheel, a driving wheel, a suspension wheel and a driving chain. Compared with the prior art, the suspension device is arranged on a tubular bus in a penetrating way and is capable of freely moving on the tubular bus, so that the tubular bus is convenient to pre-arch and the danger of high-altitude falling can be avoided so that personal injuries and equipment damage can not be generated easily and the high-altitude safe working demand is met.