Wide area X-ray and far infrared surveys are a fundamental tool to investigate the link between AGN growth and star formation, especially in the low-redshift universe (z<1). The Herschel Terahertz Large Area survey (H-ATLAS) has covered 550deg^2^ in five far-infrared and sub-mm bands, 16deg^2^ of which have been presented in the Science Demonstration Phase (SDP) catalogue. Here we introduce the XMM-Newton observations in H-ATLAS SDP area, covering 7.1deg^2^ with flux limits of 2*10^-15^, 6*10^-15^, and 9*10^-15^erg/s/cm^2^ in the 0.5-2, 0.5-8 and 2-8keV bands, respectively. We present the source detection and the catalogue, which includes 1700, 1582 and 814 sources detected by emldetect in the 0.5-8, 0.5-2 and 2-8keV bands, respectively; the number of unique sources is 1816. We extract spectra and derive fluxes from power-law fits for 398 sources with more than 40 counts in the 0.5-8keV band. We compare the best-fit fluxes with the catalogue ones, obtained by assuming a common photon index of Gamma=1.7; we find no bulk difference between the fluxes, and a moderate dispersion of s=0.33dex. Using wherever possible the fluxes from the spectral fits, we derive the 2-10keV Log N-Log S, which is consistent with a Euclidean distribution. Finally, we release computer code for the tools developed for this project.