Hundreds of homes were damaged in the western Badghis province in Afghanistan, bordering Turkmenistan, in the earthquake, Al Jazeera reported.
A spokesperson for the province told news agencies the victims died when roofs of their houses collapsed in the Qadis district of the province.
"Five women and four children are among the 26 people killed in the earthquake," the spokesperson said.
Media reports said that the second quake of magnitude 4.9 hit the region two hours after the first.
A senior official of the Ministry of State for Emergency Affairs confirmed the death toll and added that more than 700 houses had been damaged, Al Jazeera reported.
The earthquake also inflicted damage on the residents of Muqr district in the province but details were still unavailable, he said.