Abstract: The present invention relates a buffer structure of portafilter, comprising: an outer shell, having a first space and a second space in the internal thereof; a inner shell, being disposed in the second space and having a third space with at least one passage the internal thereof; a filter, being connected to the outside of the inner shell by a combination unit thereof; a positioning unit, being disposed in the third space and connected to the bottom of the inner shell for supporting; a buffer unit, being disposed in the third space and connected to the positioning unit; an elastic unit, being disposed in the third space, and connected to the buffer unit; and a moveable piston, being connected to the elastic unit.