The invention discloses a software building method and a software building system for supporting loosely coupling. In the method, a building configuration interface file corresponding to a functional module needed to be built is applied in a created building execution entry file to define a basic building function, and a building interface method is defined in the building configuration interface file corresponding to the functional module needed to be built, wherein the content of the building interface method comprises performing logic calling on a corresponding basic building method through a building configuration file. Compared with the prior art, environmental parameters and the like which are required by the functional module can be configured flexibly through the building configuration interface file in the execution entry file, the building of the other functional modules cannot be influenced, and maintenance is simple. By adding a building configuration interface unit into a building configuration unit and a building execution entry unit, the system reduces the degree of coupling of building of the modules in software engineering and improves the flexibility of a building system of the software functional modules.