Charshanga is located at an altitude of 265 meters on the banks of the Amu-Darya River, which forms the border with Jowzjan Province, Afghanistan. The Afghan town of Qarqin is on the opposite side of the river. Charshanga is near the eastern end of Lebap Province, and indeed all of Turkmenistan. The plains surrounding the river are quite flat. Near the river the land is quite fertile and arable, supporting some farming, but further from the river the land is arid. To the northeast the Köýtendag Range rises dramatically, including Turkmenistan's highest mountain, Aýrybaba, at a height of .