The invention relates to the field of civil engineering, in particular to a soil retaining method for prestressed hollow piles. The method is characterized by comprising the steps that all the prestressed hollow piles are sequentially sunken in order; the last but one prestressed hollow pile is sunken to the position which is 0.3 m away from the ground elevation, and a circular soil retaining steel plate is horizontally arranged on the surface of a pile top sealing plate and fixed through spot welding; the last prestressed hollow pile is hoisted and is in butt joint with the last but one prestressed hollow pile; a pile sunken elevation mark is made on a pile body of the last prestressed hollow pile; and the last prestressed hollow pile is sunken to the designed elevation. By arranging thesoil retaining steel plate at a pile joint of the last pile at the pile foundation engineering construction stage, pressure soil and underground water are prevented from entering a pile core of the last pile, and a pile hole anchor bar can be directly mounted without removing soil when earth is excavated into a foundation pile hole subsequently. Underground water is completely prevented from seeping into a structural bottom plate via the pile hole through the soil retaining steel plate, and basement leakage is also prevented to a certain extent.