Abstract: Construction of deep foundation pit will have adverse effect on the safety of surrounding soil mass, re? taining structure and environment. Monitoring and measurement of ground surface settlement, building settlement,deep horizontal displacement of wall, horizontal displacement and vertical displacement at the top of wall and axial force of strut are conducted for the deep foundation pit of the Foshan-Dongguan intercity railway, and a thorough analysis on the monitoring results is taken. The results show that: at the initial stage of foundation pit excavation, the lateral displacement of wall presents cantilever bending shape, the maximum horizontal displacement occurs near the top of wall and it goes downward and occurs at the bottom of foundation pit with the increase of excavation depth;the vertical displacement develops rapidly and the horizontal displacement is about 65% of the total displacement at the top of wall within 60-120 days of foundation pit excavation, the displacement is more and more slowly after 120 days of foundation pit excavation; the axial force of strut increases with the increase of depth of foundation pit exca? vation, and the axial force of all struts reaches the maximum value after the completion of foundation pit excavation.