Abstract: The sealing device includes a bag conveying mechanism, a sealing module, and a module conveying mechanism. The sealing module includes a base and an actuator, and a first sealing block and a second sealing block arranged on the base. The actuator is configured to open and close the clamping opening and includes a push rod and a horizontal actuation track. When the sealing module is moved along the conveying path of the module conveying mechanism, the horizontal guide post slides along the horizontal actuation track, and the horizontal actuation track drives the push rod via the horizontal guide post to move horizontally. Thus, the clamping opening is opened or closed.