Mongolian is the official national language of Mongolia, where it is spoken by nearly 2.8 million people (2010 estimate), and the official provincial language of China's Inner Mongolia Autonomous Region, where there are at least 4.1 million ethnic Mongols.n the People's Republic of China, Mongolian is a co-official language with Mandarin Chinese in some regions, notably the entire Inner Mongolia Autonomous Region. The traditional alphabet has always been used there, although Cyrillic was considered briefly before the Sino-Soviet split.