China (mainland) (B), India, Laos, Mongolia (B), Myanmar, Russia (Asian) (B), Russia (Central Asian) (B), Thailand, Vietnam.
Vagrant to Nepal.
Breeds eastern Russia (from Krasnoyarsk east through Transbaikalia to Khabarovsk region) and adjacent northern Mongolia, and in north-east, central and southern parts of China (south to eastern Qinghai, south-western Gansu, Sichuan and Guangxi). Non-breeding southern and south-eastern Asia.
 
Population
Estimated population is unknown (2010).
Chinese Bush Warbler (Locustella tacsanowskia) [XC468333]
by Frank Lambert from Bol'shaya Rechka, Irkutsky District, Irkutskaya oblast', Mongolia (song)
Chinese Bush Warbler (Locustella tacsanowskia) [XC483563]
by Sebastian Andrejeff from , Mongolia (call)
Subspecies
No subspecies.
In China, birds from eastern Qinghai have been described as subspecies netrix and those from Guangxi as chui. However, this species is variable in colour tones, and naming of geographical subspecies considered unwarranted.