The invention relates to modularization equipment and a method for connecting principal and subordinate module thereof. The equipment includes a principal module and a subordinate module, wherein address wires requiring low level signals of the subordinate module interface of the principal module are earthed through address wires; all address wires of the subordinate module interface of the subordinate module are connected with high-level through resistors. The method only pulls-down the addresses required to set low level in the principal module, but pulls-up all addresses in the subordinatemodule, so that the high-level of subordinate module interface is not limited by the principal module, subordinate modules set with different high-levels are connected to the principal module and cannormally work, thereby resolving the problem that the address interface high-level of the subordinate module is not matched with the principal module; meanwhile, the principal module using different platforms can adopt a same subordinate module, and the module portability and compatibility between modules are improved, thereby greatly shortening product developing cycle and saving product development cost.