The invention provides a method for applying continuously adjustable uniaxial stress to semiconductor samples at a low temperature. The method comprises the following steps: choosing a piezoelectric ceramic actuator which can regulate applied stress by changing the bias voltage of piezoelectric ceramics; fixing two U-shaped red-copper blocks used at two ends of the piezoelectric ceramic actuator to fix samples and conduct heat; connecting a red-copper heat-conducting wire with one red-copper block to conduct heat uniformly and rapidly; using super glue to bond two ends of a semiconductor sample to the two U-shaped copper blocks; and changing the bias voltage of the piezoelectric ceramics on the piezoelectric ceramic actuator so as to apply continuously adjustable uniaxial stress to the semiconductor sample. The method has the advantages that the magnitude of uniaxial stress is continuously adjustable in double directions and can be measured; the sample is rapid and accurate in temperature reduction; and a device is small in occupied volume and easy to operate and can be perfectly combined with a low-temperature device.