The invention discloses a detecting device for pile foundation static load. The detecting device comprises a lifting jack, force collecting I-shaped steel, foot-pad clump weights, force bearing I-shaped steel and press pile clump weights; the lifting jack is placed at the top of a to-be-detected pile foundation, the lifting jack is coincided with the central axis of the to-be-detected pile foundation, the foot-pad clump weights are placed on two sides of the to-be-detected pile foundation, the force collecting I-shaped steel is arranged above the lifting jack, the center of gravity of the force collecting I-shaped steel is located on the central axis of the lifting jack, the long edges of the force collecting I-shaped steel are parallel to the long edges of the foot-pad clump weights, the multiple force bearing I-shaped steel is arranged on the foot-pad clump weights, the press pile clump weights are arranged on the force collecting I-shaped steel, the number of the force collecting I-shaped steel is 1.2 times as much as the pile foundation design bearing capacity after the pile foundation design bearing capacity is divided by single weight of the press pile clump weights, and the press pile clump weights are stacked in a pyramid shape. The detecting device and a detecting method for the pile foundation static load have the advantages of being easy to carry, uneasy to deviate the center of gravity, safe and reliable and good in detecting effect.