The utility model discloses a loading joint construction for spread foundation full scale test, including loading device, loading device is the installation of hydraulic pressure static pressure, and loading device keeps silent and accompanies biography power concrete pile, passes power concrete pile below and is provided with the short column, is fixed with cow -leg pillar to the side of the short column, cow -leg pillar's shape is right trapezoid, and wherein, cow -leg pillar's go to the bottom and the side of short column are connected, and cow -leg pillar's right angle waist and the up end of short column are located same horizontal plane, short column, cow -leg pillar top all are connected with the built -in fitting, be provided with pressure sensor in the built -in fitting, the external pressure measurement instrument of pressure sensor. The utility model discloses cow -leg pillar has been increased to the side of the short column for loading device not only can implement the axle center loading to spread foundation, can also implement eccentric loading, use hydraulic pressure static pressure stake machine to replace reaction frame jack system, improve the experimental efficiency to big the ratio of width to height spread foundation full scale test effectively, saved the cost and reduced the time.