Vertical multiphase flow gradient curves for four wells in X- field were constructed using actual flowing pressure survey data, the vertical multiphase flow gradient curved were also constructed using appropriate multiphase flow vertical correlations by utilizing reservoir, well and PVT data Multiphase flow vertical gradients in oil wells are needed for the design of artificial lift systems as well as for the design of well flow productivity. These gradients are measured in the well directly during bottom hole flowing pressure surveys. But in most cases these measurements are not available during the installation of the artificial lift systems. Similarly, these measurements cannot be made if the well is not flowing. In this study we analyzed pressure gradient (pressure vs. depth) for four wells under gas lift. In addition, an investigation was made in order to find the best suitable correlation among the existing correlation in the literature for Y- reservoir oil wells.in additional software was used to optimize the best correlation close to actual flowing pressure gradient. These multiphase flow curves were utilized in the preparation of the vertical lift performance (VLP) for the four wells which are used for the determination of the prosper well design, gas lift design. The actual measured vertical flow pressure traverses trend for most wells matches very well with existing multiphase vertical pressure correlations depending on each well. Nevertheless, the difference between correlation matches for studied wells affected by parameters like the WC%, flow rate, bottom hole flowing pressure and free GOR at surface, accordingly, the selection of the suitable multiphase flow correlation was made by comparing the actual flowing pressure gradient with the existing correlations.