The avalanche hit a battalion headquarters at Gyari in Siachen sector at around 6 am, TV news channels reported.
Chief military spokesman Maj Gen Athar Abbas said a rescue operation was underway. Helicopters, sniffer dogs and additional troops had been sent to the area to help with the rescue in the desolate region, a military statement said.
The incident occurred at a spot near Skardu in the eastern Karakoram mountain range. Some reports suggested that 135 soldiers, including a colonel, had been hit by the avalanche. There were reports of casualties but these could not be independently confirmed.
Gyari is home to an important battalion headquarters and at one time, up to 3,000 soldiers were based in the area. Following the ceasefire along the frontiers in Jammu and Kashmir, both India and Pakistan reduced troop levels.
The Siachen glacier is known as the world?s highest and coldest battlefield. More Indian and Pakistani soldiers have been killed by adverse weather than combat in the sector.