There is provided a line redundant method for implementation of line switching in a switching matrix, including the bridge step of outputting a data signal to a plurality of redundant lines in the switching matrix, and the selector step of selecting only a data signal, of a plurality of data signals input from another switching matrix other than the switching matrix through the plurality of redundant lines, which is input through a redundant line required in the switching matrix, and not selecting the data signals input to the switching matrix through the lines other than the required redundant line. A line redundant system for implementing this method is also provided.