The invention provides a settlement calculation method of a grid-type diaphragm wall bridge foundation in a soft soil foundation. According to the method, the structural characteristics of the grid-type diaphragm wall foundation itself in the soft soil foundation are taken into account; based on the foundation settlement characteristics, calculation of the frictional resistance on the outer side of a wall body is deduced, meanwhile the concept of equivalent shear stiffness is put forward and used for calculating the frictional resistance on the inner side of the wall body, and finally based ona load transfer method, the foundation settlement amount under various levels of load can be calculated by means of iterative calculation. According to the method, it is unnecessary to conduct special geotechnical engineering investigation, and the method provides a scientific basis for engineering design and construction of the soft soil foundation to which the novel grid-type diaphragm wall bridge foundation are applied.