PURPOSE: A stirling cooler is provided to prevent the performance deterioration caused by the friction loss and wear of the cooler using a piston and to increase efficiency by alternating an operating member correspondent to the piston with a diaphragm. CONSTITUTION: A stirling cooler is composed of a displacer(30) for reciprocating between low and high temperature parts; a regenerator(40) for being an actuating fluid passage between the low and high temperature parts and temporally storing and regenerating heat of the actuating fluid; a diaphragm(50) for corresponding to the displacer and inducing the compression and expansion of the actuating fluid; a driving unit(60) connected and installed to the diaphragm to excite the diaphragm to the predetermined exciting force and operation displacement; and a case(70) for sealing the high-pressure actuating fluid. Two diaphragms are installed symmetrically. The driving unit is a piezoeletric actuator.
