Abstarct: One of the important parameters in tunnel excavation in urban areas using Earth Pressure Balance machine (EPB) is tunnel face pressure since applying the pressure lower or higher than balance limit causes collapse or blow out in tunnel face or ground surface respectively, so that it results stoppage in excavation, settlement or blow out in ground surface, damage to buildings near tunnel and increase in costs. Required pressure for tunnel face support is controlled using screw conveyor rotation speed as a function of machine penetration rate. Adequate pressure for face support is estimated using empirical-analytical(limit equilibrium and limit analysis) and numerical methods, by considering tunnel geometrical parameters, traffic and construction loads, underground water level, soil physical and mechanical parameters and overburden height. In this research, face stability in Abuzar surface water collecting tunnel has been studied by using empirical-analytical and numerical (finite element) methods and then values of these methods have been compared. Finally, sensitivity analysis to study the influence of different parameters on face pressure, has been done on these parameters and so underground water and cohesion showed the most influence in face support pressure.