The Egyptian dense urban cities around the Nile and in the Delta region are famous for the high rise buildings due to the lack of land for development. Due to the low bearing capacity of soil encountered in these regions, deep foundations are usually utilized for high to medium rise buildings. Continuous Flight Augers (CFA) piling technique by far the most used technique in those regions due to its minimal vibration, low noise and low cost, beside its quick installation compared to other drilled shaft techniques.Despite all this advantages drilling of these piles can cause settlement and distresses to the adjacent structures especially if the drilling in close vicinity to the adjacent structures. In this paper threedimensional (3-D) finite element analyses were conducted to understand the factors affect the magnitude of surface settlement due to CFA drilling. The influence of the drilling depth, pile location and soil parameters are systematically studied. The analysis shows that the settlement during the unfavorable CFA drilling is similar to an inverted cone with maximum settlement at the pile location and decreases with distance. The surface settlement profile is extended to a distance of about 0.7 of the depth at which overflighting occurred. It is also observed that sand relative density has a significant effect on the magnitude of settlement in the vicinity of CFA drilling. Finally, pile group drilling was investigated to gain insight into the effect of pile group on the adjacent structures.