Stability analysis of three mostly constructed Reinforced Soil Wall (RS Wall) heights (say, 8, 7.2 and 6.4 m) under varying soil conditions have been studied. Apart from internal stability of RS Wall, external stability and Global stability analysis are also important for the performance of the RS Wall structure and have been studied in this paper. In the paper, the performance of the structure for both in the cases of subsoil conditions, that is soil profile consisting cohesive or non-cohesive soil have been studied. Based on the requirement of bearing pressure and available bearing capacity of existing ground, the requirement of Ground Improvement also evaluated. An economic mode of Ground Improvement such as with Prefabricated Vertical Drain, Woven Geotextile and Geocell have been studied. A parametric study has been done varying friction angle of Reinforced Fill, unit weight, Heights of RS Wall, length and Grade of Geosynthetic Reinforcements, and methods of Ground Improvement under different subsoil conditions. For the analysis of Reinforced Soil design, both LEM and FEM methods have been used. In the case of LEM, we have designed through excel spreadsheet, ReSSA Software, GEO5 Software and PLAXIS 2D Ultimate (version 2021) have been used. The study of this research may be helpful to the practicing engineers who would design Reinforced Soil Wall of various heights under varying Geotechnical conditions of Subsoil.