Abstract: This papor reporis the progress in Joule-Thomson cooler using gas mixture as a working substance,Two important thermedynamic pararneters,isothermal Joule-Thomson effect and the normal boiling ternperature,are caculated to compare with the experimental results,In addition,the enthapy vs,temperture diagrams of a specific gas mixture and pure nitrogen gas in different working pressures are given,The theoretical and exporimental results both show that the potentlal of Joule-Thomson ccoler with gas mixture will be more efficient than that of Joule-Thomson ccoler with pure nitrogen gas.