The invention relates to the field of a refrigerator, and discloses a thermally-driven 
stirling cryocooler. The thermally-driven 
stirling cryocooler comprises an engine, a refrigerator, a 
discharger and a 
harmonic oscillator; the engine comprises a hot end 
heat exchanger, a first heat accumulator and a first 
room temperature heat exchanger which are sequentially connected; the refrigerator comprises a second 
room temperature heat exchanger, a second heat accumulator and a cold end heat exchanger which are sequentially arranged, wherein the engine is internally provided with a first thermal buffering cavity, the refrigerator is internally provided with a second thermal buffering cavity, the upper end of the first thermal buffering cavity is connected with the hot end heat exchanger, and the lower end of the first thermal buffering cavity is connected with the first 
room temperature heat exchanger; the lower end of the second thermal buffering cavity is connected with the cold end heat exchanger, and the upper end of the second thermal buffering cavity is connected with the second room temperature heat exchanger; the engine and the refrigerator are relatively arranged up and down, a shared cavity is formed between the engine and the refrigerator, and the 
discharger and the 
harmonic oscillator are both arranged in the cavity in a contraposition way. The 
discharger provided by the invention can be operated at the room temperature end, the design and 
processing difficulty of the discharger can be reduced, and the vibration of the 
system can be reduced.