A load lock chamber provided between a port that accommodates an object to be processed and is maintained at an ambient pressure, and a process chamber that is maintained at a reduced pressure or vacuum environment and performs a predetermined process for the object, said load lock chamber replacing an atmosphere in said load lock chamber and delivering the object between the port and the process chamber includes a first load lock chamber that includes a first holder for holding the object received from the port, and a second load lock chamber that includes a second holder for holding the object received from the process chamber, wherein the first holder holds more objects than the second holder.