"A patrol party of army came under an avalanche in southern area of Siachen glacier yesterday," Udhampur-based defence spokesman Colonel S D Goswami said on Saturday.
A rescue operation was launched immediately and 15 soldiers were saved, he said.
Regimental Medical Officer Captain Ashwini Kumar could not be saved and his body was retrieved from under the avalanche, he said.
Capt Kumar, from 3 Ladakh Scouts, was a bachelor and hailed from Patiala in Punjab.
General Officer Commanding of the Army's Northern Command Lt General D S Hooda has expressed grief over the loss of the officer, he said.
The spokesman said the Army commander has conveyed his condolences to the bereaved family. 41824