A pressing device is provided, including: a main body, including a chamber; a pushing assembly, including a retractable mechanism movably inserted within the chamber, a first pushing board connected with the retractable mechanism and a restricting member embedded within the chamber and blocking the retractable mechanism from moving out of the chamber; a hydraulic mechanism, including a tube body which is connected with the main body and communicated with the chamber, a driving rod movably inserted within the tube body and a piston driven by the driving rod, the piston being configured to drive fluid to flow in or out of the chamber. Another pressing device is further provided, differing from the pressing device described above in that: the main body further including a channel, a wall of the chamber including at least one recession which is communicated with the channel.