A conveying device includes a base, a sliding mechanism and a bearing mechanism. The base includes a mounting plate and a fixed bracket fixed on the mounting plate. The sliding mechanism includes a bottom plate slidably mounted on the mounting plate, a mounting platform fixedly mounted upon the bottom plate, a conveying assembly and a driver. The conveying assembly includes a driving wheel, a driven member and a conveying belt sleeved on the driving wheel and the driven member. The driver is mounted on the bottom plate and connected with the driving wheel. The bearing mechanism is slidably mounted on the mounting platform, and fixed with the conveying belt. The driving wheel and the driven member are oppositely and rotatably mounted on the bottom plate, the fixed bracket is positioned adjacent to the driven member and fixed with the conveying belt.