To diagnose the electron temperature of a Z-pinch plasma,the ratio between the dielectronic recombination satellite line for argon to the w-resonance line for lithium-like as a function of the plasma temperature is analyzed.The spectral emission pattern of helium-like argon together with the associated satellite line from lithium-like argon have been measured with an X-ray elliptical curved crystal spectrometer on a Yang accelerator.The spectrum of argon-puff Z-pinch plasma is described by a curved mica crystal analyzer and the helium-like resonance line w,satellites j,k,q,magnetic quadrupole M2 line,intercombination line y,forbidden line z and the cold Kα line of argon are recorded with an X-ray film.Then,the line ratios between the dielectronic recombination satellites (j+z,k) to the w-resonance line are calculated,obtained results show that the electron-temperatures of the plasma are 960~1 060 keV.The theoretical models are in agreement with the experimental results well,which supports the conclusion that proposed method can be used in a temperature diagnostic method for plasma.