所谓“双认证”是指我国内地有关机构出具的涉外公证书或其他证明文书在送国外使用前，办理好我国外交部领事司或其委托的地方外办的领事认证后，还需按文书使用国要求办理该国驻华使领馆的领事认证，方可被文书使用国接受。

The so-called ‘double authentication’ refers to the requirement that before foreign-related notarization certificates or other proof documents issued by relevant institutions in mainland China are used abroad, they must be authenticated by the Consular Department of the Ministry of Foreign Affairs of China or the local foreign affairs office entrusted by the Ministry of Foreign Affairs, and then they need to be authenticated by the consular office of the country’s embassy or consulate in China according to the requirements of the country where the documents are to be used before they can be accepted by the country where the documents are to be used.