Gaplaňgyr or Kaplankyr is a mountain plateau and nature reserve (zapovednik) of northern Turkmenistan.

It is a place for the protection and restoration of indigenous flora and fauna, it is located on the Gaplaňgyr Plateau at the southern spur of the Ustyurt Plateau at the border with Kazakhstan and Uzbekistan in the north-west of Daşoguz Province.

Protected rare species of animals found in the reserve include, Central Asian gazelle, the Ustyurt Mountain sheep, honey badger as well as substantial population of the Saiga antelope that migrate here from Karakalpakstan in the winter.

Plants include the Khiva thistle, Turkmen tulip, Antonia's gypsophila, Karelin sand acacia, and 55 other endemic species.

The Gaplaňgyr Nature Reserve also incorporates two sanctuaries: Sarygamyş Sanctuary, which was established in 1980 as a lake-coastal ecosystems, and Şasenem Sanctuary, which was established in 1984 for the preservation of stony desert and the Turkmenian kulan.