The invention provides a lowering device for a
pile foundation reinforcement cage. The lowering device comprises an inner cylinder, an outer cylinder, a limiting plate, a limiting column and a
rope; the outer cylinder is slidably arranged on the outer wall of the inner cylinder in a sleeving mode, the limiting plate limits the outer cylinder, and the limiting column is used for controlling movement of the limiting plate; the
rope is connected to the top end of the limiting column and used for driving the limiting column to rotate. The limiting plate is extruded through the limiting column, one end of the limiting plate extends out of the inserting opening, the outer cylinder is locked on the outer side wall of the inner
barrel, then the position of the annular space is locked, a
steel bar head at the lower end of a
steel bar column is inserted into the annular space, and the
steel bar column and the outer cylinder are bound and fixed through a binding wire. And in the lowering process, the steel bar head is hidden, so that the steel bar head is prevented from frequently colliding with the inner wall of the
pile foundation hole, the effect of protecting the inner wall of the
pile foundation hole is achieved, and the lowering difficulty of the steel bar cage is reduced. The limiting plate retracts into the inner cylinder, and locking of the limiting plate on the inner cylinder is relieved; and the inner cylinder can be taken out through the
rope, so that the inner cylinder is recycled.