An accurate theoretical method based on matrix optics and diffraction theory is developed for predicting the performance of the extremely long compound refractive Xray lens. The size of focus, effective aperture of focusing Xray beam and the intensity gain in focus are derived. Then several PMMA extremely long parabolic compound refractive Xray lenses with the curvature radius of 50 μm are fabricated by means of deep Xray lithography. Finally, the focusing performances of the PMMA extremely long parabolic compound refractive Xray lenses are measured and analyzed under 8 keV monochromatic on the 4 W, 1 A beamline of Beijing synchrotron radiation facility (BSRF). According to the experimental results, it is shown that the PMMA extremely long parabolic compound refractive Xray lenses promise a good focusing performance under hard Xrays.