a crossbar switch system with redundancy has n + 1 cross - bar switches . a first cross - bar switch has first outputs of each of a plurality of nodes applied to n input terminals thereof , an th cross - bar switch has nth outputs of each of the nodes applied to n input terminals thereof , and second to nth cross - bar switches each have first to nth selection circuits , which are provided at respective input terminals thereof , to each of which are input mutually adjacent th and ith outputs among outputs of each of the nodes . each node has n selection switches , which are provided at input terminals thereof , to each of which are input jth outputs of two mutually adjacent cross - bar switches among the first to th cross - bar switches . in response to a selection control signal output from a failure processing circuit that executes crossbar switch failure processing , each of the selection circuits selects and outputs one of its two inputs .