Deep Excavations are required to facilitate underground metro structures such as underground stations, cut & cover tunnels, and underground ramps, Launching/Retrieval shafts. To facilitate deep excavations a temporary/permanent lateral supporting system is generally required to prevent ground settlements because of the underground excavation or construction activities. Diaphragm Wall/D wall is generally accepted as a temporary/lateral permanent support system with or without lateral supports. For a D Wall supported excavation system, the first stage is the construction/Installation of D Wall after guide wall construction. The installation of D Wall is achieved by excavation of D Wall panel trench with the help of suitable machinery called D Wall Grabber/mill. During excavation, the panel trench will be filled with bentonite/polymer slurry of suitable consistency, viscosity, and unit weight. The height of slurry is usually maintained at a height above water table. As the depth of D wall is significantly deep and passes through multiple soil layers, the instability of slurry filled trench is quite common. Several Analytical and Numerical methods are available to investigate the stability of D wall slurry trench. In this paper an underground D Wall Excavation for an underground station is considered. The stability of the D Wall trench is evaluated based on analytical methods namely Limit Equilibrium without arching effect, Limit Equilibrium with arching effect and numerical method based on 2D Finite Element Method are considered. Plaxis 2D, which is a finite element-based numerical software is used for the numerical method. The results indicate that considering arching effect in limit equilibrium method significantly increased the FOS by 25–50%. FEM 2D approach showed around 30% reduction in FOS in clay layers and 6–24.6% increase in FOS in sand layers compared to Limit Equilibrium without arching effect. Arching effect is more significant at shorter trench depths and gives optimistic height of slurry for shorter trench depths. Shorter panel lengths give higher FOS in case of limit equilibrium with arching effect. Panel lengths have no effect in 2D FEM method and Limit Equilibrium without arching effect.