The capability of CLOS network to support connection requirements of conference is discussed in this paper.A scheme to combine an introducing network and a conference network is proposed.This scheme fits well to today’s network practice with the intensive use of the cross connection equipment. It is proved that
when the ports of conference network assigned to each conference are in order
the necessary and sufficient condition of conference rearrageable nonblocking is mn+ 1.An algorithm to select the routing set for each conference is constructed to realize the conference non-blocking and conference independent routing as well for the cases of m n+ 2.