We examine in this paper how the controlling shareholders of listed companies use we-media information disclosure to adjust the change of stock price in private placement financing to obtain additional earnings. It is found that the controlling shareholders tend to release we-media information frequently during the preparatory period of the private placement in order to raise the stock price and attract the attention of external investors. Moreover, when the private placement does not include controlling shareholders, it is more significant to increase the price of shares by increasing the number of Weibos. However, during the pricing period of private placement, listed companies whose private placement targets include controlling shareholders will significantly reduce the amount of information published by we-media, so as to lower the stock price and help controlling shareholders to purchase private placement shares at a lower price. The further analysis shows that the institutional investor's shareholding in listed companies has a significant restraining effect on the controlling shareholder's behavior of driving down the stock price during the pricing period. This study discusses from a new angle of we-media information disclosure, confirms that in the process of private placement, the controlling shareholders of listed companies both use information disclosure through the we-media to attract attention, meet the financing motivation, and reduce the cost of controlling shareholders to participate in the purchase, meet the self-interested motivation. However, institutional investors can effectively supervise the self-interested behavior of controlling shareholders in this process. The study provides useful enlightenment for strengthening the supervision of information disclosure of listed companies in private placement and protecting the interests of small and medium-sized investors.