Pressure-density-temperature (P蟻T) measurements of five natural gas mixtures that represent Qatar鈥檚 North Field natural gas reservoirs were carried out at temperatures from (250 to 450) K and at pressures up to 65 MPa by using a Anton Paar庐 (Graz, Austria) vibrating tube densimeter DMA 512P high-pressure cell. Total 20 isotherms from 250 K by 10 K intervals up to 450 K were measured. Experimental density data were compared with two main industry standard equations of state (EOS) namely AGA8-DC92 EOS and GERG2008 EOS. Comparisons of the experimental data with respect to AGA8-DC92 EOS and GERG2008 EOS resulted in prediction deviation ranges of (0.05 to 鈭?.5)%and (0.25 to 鈭?.5)%respectively.