This paper focuses on volatility spillover effects and considers the issue of how to measure the connectedness of networks among financial firms.To assess the network connectedness offirms from different industries,we proposed a novel procedure and applied it to 20 leadingfinancial institutions from four industries in China's stock markets.The results show that the total connectedness of the Chinese financial system was much higher during the stock market crisis between June 2015 and February 2016 than during stable periods of economic development.This analysis can be used to determine whichfirms play a dominant role in risk transmission throughout the entire system.It is suggested that the government should provide targeted regulatory policies to particular types of firms.