A dual-channel, co-axial, focusing X-ray crystal spectrograph is developed for spectroscopy of the Z-pinch plasmas. The spectrograph uses a uniform-dispersed crystal (the linear dispersion is a constant) and a spherical crystal as the dispersion element and a double-film box as the detector to achieve the simultaneous measurement of the time-integrated spectra of the plasmas in almost the same spectral range. The experiment is carried out on the “Yang” accelerator at Chinese Academy of Engineering Physics (CAPE) and the H-like and He-like emission lines of Al Z-pinch plasmas are obtained. The results show that the linear dispersion obtained by the uniform-dispersed channel, is agree with the designed value very well due to satisfying the uniform dispersion condition, and the maximum relative error is only 3.48%. Compared with the spherical crystal channel, it has the advantage of easiness and veracity for spectra identification and processing and it may be useful for the complicated spectra identification and analysis.