Abstract: The traditional single-point monitoring method based on total stations has the disadvantages of being unable to reflect the overall horizontal displacement of the steel sheet pile top, needing to lay a reference network, and requiring a large amount of manual work. The unmanned aerial vehicle(UAV)photogrammetry technology can intuitively reflect real ground object information. It has superior performance such as high precision, high efficiency, integration, and automation. Based on the Sanhu Lianjiang Avenue project in Jiayu County, Hubei Province, a method for monitoring the horizontal displacement of the steel sheet piles' top based on UAV photogrammetry technology is proposed. In this method, UAV photogrammetry technology is adopted to reconstruct the real 3D model of the steel sheet piles. The horizontal displacement of the top of the steel sheet piles is monitored based on the distance change of the measuring points in different periods. Then, the horizontal displacement characteristic law of foundation pit steel sheet piles is analyzed. The results show that the general trend is that the horizontal displacement of the top of the steel sheet piles at both ends of the foundation is small, while that at the middle of the foundation is large. The horizontal displacement of the steel sheet piles in the middle of the foundation pit is 5.85 times and 2.09 times that of the left and right ends of the foundation pit, respectively. Moreover, during foundation pit excavation, the horizontal displacement of the steel sheet piles is large. The average horizontal displacement rate is as high as 73.5 mm·d^-1. After the addition of the waist beam and transverse support structure, the average horizontal displacement rate of the steel sheet pile is reduced to 18.3 mm·d^-1. Compared with the excavation stage of the foundation pit, the average horizontal displacement rate of the sheet piles is reduced by 75.2%. The present study provides a reference for the horizontal displacement monitoring of sheet piles under similar geological conditions in the future.