The 7.8 magnitude quake struck an area between the capital, Kathmandu, and the city of Pokhara, the US Geological Survey said.
Tremors were felt across the region, with further loss of life in India, Bangladesh, Tibet and on Mount Everest.
The government has declared a state of emergency in the affected areas.
Nepali Information Minister Minendra Rijal said there had been "massive damage" at the epicentre, from where little information is emerging.
Order from Maithri
The Foreign Affairs Ministry sources report that the President Maithripala Sirisena has instructed to send an aircraft belonging to the SriLankan Airlines and another belonging to the Air Force to Kathmandu to aid the earthquake victims.
It has been stated that trained dogs will also be sent to rescue the victims along with medication for those who are injured inside the aircraft.