  We present a work in progress aimed at measuring the spectrum of the Cosmic
X-ray Background (CXB) with the EPIC detectors onboard XMM-Newton. Our study
includes a detailed characterization of the EPIC non X-ray background, which is
crucial in making a robust measurement of the spectrum of CXB. We present
preliminary results, based on the analysis of a set of Commissioning and
Performance Verification high galactic latitude observations.
