Gogoi would urge the defence ministry to review the case to ensure proper justice to the 19-year-old victim, a statement from the Chief Minister's Office said.
"The army court has been insensitive to the seriousness of the crime and has taken a lenient view," the statement said.
"Imprisonment for only three months is far less than the heinous crime committed by the armyman. The army court must have meted out deterrent punishment against the accused," it said.
An army court Monday sentenced Anil Kumar Upadhaya, a lance naik with 287 Field Regiment, to three months of rigorous imprisonment in military custody and demoted him to the rank of sepoy.
Upadhaya arrested after he was caught attempting to molest a woman in Dolopa village in Sivsagar district in July last year.