Inner Asia refers to the northern and landlocked regions spanning North, Central and East Asia. It includes parts of western and northeast China, as well as southern Siberia. The area overlaps with some definitions of 'Central Asia', mostly the historical ones, but certain regions that are often included in Inner Asia, such as Manchuria, are not a part of Central Asia by any of its definitions. Inner Asia may be regarded as the western and northern "frontier" of China proper of the former Qin dynasty and as being bounded by East Asia proper, which consists of China, Japan and Korea.

The extent of Inner Asia has been understood differently in different periods. "Inner Asia" is sometimes contrasted to "China Proper", that is, the original provinces, those with majority Han Chinese populations. In 1800, Inner Asia consisted of four main areas, namely Manchuria (modern Northeast China and Outer Manchuria), Mongolia (Inner and Outer), Xinjiang (East Turkestan), and Tibet. These areas had been only recently conquered by the Qing dynasty of China and, during most of the Qing period, they were governed through administrative structures different from those of the older Chinese provinces. A Qing government agency, the Lifan Yuan, supervised the empire's Inner Asian regions.