Neutron/density measurements have been used to derive formation porosity. While this yields acceptable results in clean liquid-filled lithologies (sands), the effects of lithology, hydrocarbon fill (gas), and formation heterogeneity in shaly sands increases the uncertainty in computed porosities. The technique of using combined NMR relaxation times and bulk density data described in this paper significantly reduces uncertainty in derived logging parameters through elimination of the neutron log. This removes the need to correct for flushed zone This paper describes the application of DMR technique in cored wells in a gas field, Western Desert, Egypt and it discusses the results obtained, limitations and benefits, along with the data acquisition requirements. Field examples demonstrate the importance of the (DMR) technique in place of the use of NMR or conventional logs separately in determining formation porosity and gas saturation in tight gas sand reservoirs. Introduction The field of interest, in the western desert of Egypt is gas-condensate field producing from the Mesozoic Lower Safa reservoir. The reservoir is classified as a tight gas reservoir due to compaction (4000m depth), very fine sand size and the presence of clay minerals (Kaolinite & Illite) which affect permeability to be in the range from 0.01 to 100 md micaceous sandstone deposited in a strongly tidally influenced estuary with 5–12% porosity and high lateral and vertical heterogeneity. Siderite locally found replacing mudstones and siltstones. Due to the high heterogeneity of the reservoir; many cores were acquired in different wells covering different reservoir units to create the proper models for porosity and permeability for the different facies. Because the first three facies units are one sand body of high Net/Gross sand and it is difficult to differentiate between them(1), It was difficult to use one log alone to define the corrected porosity. As a result, Neutron-Density cross plots were used as a trial to calculate corrected gas porosity, but the neutron log response was not reliable in this case because of iron rich clay minerals and the absorbers of thermal neutrons like Cl (chlorite), Siderite and Glauconite. Nuclear Magnetic Resonance (NMR) log is better suited to be used in combination with density log in this case rather than neutron logs because NMR tools are sensitive only to hydrogenand fluid protons and no borehole correction is needed whenever the radius of investigation is beyond caliper measurements specially incase of MRIL tool (our case), except in case of very high saline mud, which will affect NMR measurements.(2, 3) In the following section we will present the derivation of Density-Magnetic Resonance Porosity (DMRP) formula (Ref. 4, 5), calibrate this formula with the stress corrected core porosity. We will then apply the DMRP formula in our reservoir of interest and discuss the results and conclusions.