According to the Company Law, investors can inject capital into subsidiaries through long-term equity investment. Specifically, the parent company can complete the capital injection by debiting the long-term equity investment account and crediting the paid-in capital and capital reserve account. At the same time, the wholly-owned subsidiary of a wholly state-owned company, that is, the secondary wholly-owned subsidiary, should also belong to a limited liability company wholly owned by a legal person. In the actual operation process, in addition to capital injection, it is also necessary to provide copies of ID cards, mobile phones, mailboxes and other related materials of legal persons, supervisors and financial contacts. Complete the registration of subsidiaries.