Stability is one of the key issues for industrial ecosystems and industrial communities. By introducing the “structural holes” thinking in social networks theories, a weighted connectance is proposed for industrial communities. Compared with non-weighted connectance, the weighted connectance can reflect different levels of importance to different nodes and connections. Cases study of the Kalundborg and Anyang industrial ecosystems illustrate that the weighted connectance can serve as a quantitative indicator for evaluating industrial ecosystems or eco-industrial parks.