[en] An in-pile creep machine of HANARO was designed and fabricated for the measurement of uniaxial deformation of zirconium cladding tube working at the conditions of <400 .deg. C, and 2kg/mm². The creep machine mainly made of 304 stainless steel consists of bellows assembly, grips, yokes, a push rod, heater and bearing. The creep machine heater has two sections which heating element is silicon carbide with aluminium oxide insulator. Thermocouples are attached to specimen and heater for the temperature monitoring and controls. Inner temperature of the creep capsule is also controlled by gas flowing into the main chamber of the creep machine. The bellows assembly is isolated to the main chamber and controlled by an external gas pressure. The load and displacement of the zirconium specimen was determined by a pressure gauge and a linear voltage differential transformer, respectively. The load-displacement relationship was automatically converted into stress-strain curve by a computerized machine. The performance test of the creep machine in out-of pile conditions showed that the resultant stress-strain curve was well agreement with the results determined by a standard tensile test machine