Transport container automatic clamping mechanism

An automatic clamping mechanism capable of automatically securing and releasing a wafer transport container to or from a manufacturing apparatus and having a small height dimension is provided at low cost. A wafer transport container is placed on a container placing table. A semiconductor wafer is loaded into the manufacturing apparatus main body from a wafer loading port while being placed on a container base part of the wafer transport container. An automatic clamping mechanism generates a press force component in a vertical direction at the wafer transport container and secures the wafer transport container to the container placing table by bringing claw parts of a plurality of clamping claws into contact with an inclined contact surface provided on a container lid part of the wafer transport container and pressing the inclined contact surface in a substantially horizontal direction.