Guoyu (國語, Wade-Giles: Kuo-yü) can refer to:

• Standard Mandarin, the standardized spoken Chinese language. This meaning was added in Japan (kokugo in Japanese) to refer to the language of a nation state and loaned into Chinese.
• a classical history book of ancient China. See Guoyu (book).
• the language the Emperor spoke. It usually referred to non-Chinese languages. It was the Xianbei language during the Northern Wei Dynasty, Khitan during the Liao Dynasty, Jurchen during the Jin Dynasty, Mongolian during the Yuan Dynasty and Manchu during the Qing Dynasty.