New data of high pressure density have been reported for p-xylene pure component and its binary mixtures with dimethyl carbonate, diethyl carbonate, n-octane and n-decane at (288.15, 298.15 and 308.15) K and (0.1, 5, 10, 20, 30 and 40) MPa and they have been compared with those available in the literature. The high pressure density has been correlated and predicted using a modified Tait equation and Nitta Chao group contribution model respectively. The derived thermophysical properties such as isothermal compressibility (jT), isobaric thermal expansivity (alpha(p)) and internal pressure (pi) have been also calculated. (C) 2013 Elsevier Ltd. All rights reserved.