The maximum subgraph problem (MSP) of a graph is the estimation of the greatest number of edges in the induced subgraph of all subsets of the vertex set of the same cardinality. The Knodel graph W-Delta,W-n of n vertices and the highest degree Delta lies in [1, left perpendicularlog(2)(n)right perpendicular], where n is even, is a minimum linear gossip graph and with minimum broadcasting. In this paper, we will obtain the maximum subgraph of the 3-regular Knodel graph W-3,W-n, n >= 16, n is even, and thereby obtain its wirelength.