By taking the listed companies of A-share ultimate government ownership during 2004—2011 as research objects, by using CAPM, Gordon, OJ and ES Model, their average equity capital cost is estimated, the influence of the length and width of governmental equity and ultimate ownership structure inside state-owned enterprise groups on equity capital cost is tested, and the analysis shows that the equity capital cost of the listed companies of the ultimate ownership of central government is lower than that of the listed companies of local government ownership, that there is an obviously negative correlation between ultimate ownership structure length and equity capital cost, however, there is not a significant correlation between ultimate ownership structure width and equity capital cost, thus, comparing with the extending control chain length, it is more beneficial for a government to control the listed companies via multi-channel, as a result, a government should decease its intervention with the listed companies and meanwhile should not let the ultimate ownership structure length extend limitlessly.