China (mainland), Indonesia, Japan, Mongolia, North Korea, Papua New Guinea, Philippines, Russia (Asian), Russia (Central Asian) (B), South Korea, Taiwan (China).
Vagrant to Denmark, France.
Population
Estimated population is unknown (2010).
Gray's Grasshopper Warbler (Helopsaltes fasciolatus) [XC68573]
by Albert Lastukhin from Bol'shaya Rechka, Irkutsky District, Irkutskaya oblast', Indonesia (song)
Gray's Grasshopper Warbler (Helopsaltes fasciolatus) [XC381993]
by Per Alstr\u00f6m from Hulunbeier Shi, Neimenggu Zizhiqu, China (song)
fasciolata (Gray, 1860) - Breeds south-central Siberia (from east of upper R Ob') east to south-eastern Russia (Amurland, Ussuriland) and north-eastern China. Non-breeding Philippines, Sulawesi, Moluccas and western New Guinea.
amnicola Stepanyan, 1972 - Sakhalin, southern Kuril Islands and Hokkaido. Winters in Philippines. Considered by some authors to be a distinct species, Sakhalin Grasshopper-warbler (Locustella amnicola).