"The army will now assist the authorities at the Kaziranga National Park in protecting the rhino," park director S.N. Buragohain told The Associated Press.
The soldiers will live in tents in the park, he said.
The 267 square mile park, about 135 miles east of Gauhati, the capital of Assam state, is home to more than 1,800 of the world's estimated 3,000 one-horned rhinoceroses.
Poachers killed about 20 rhinos in the park last year and six have been killed so far this year.
"The army's presence is expected to keep poachers away. This is good news for us," Buragohain said.
Soldiers have also been asked to be part of anti-poaching drives in at least six other national parks and sanctuaries in the state.
Gangs of armed poachers kill rhinos for their horns, which many believe have aphrodisiac qualities and are used in medicines in parts of South and Southeast Asia.
Rhino horns are also popular in the Middle East, where they are fashioned into handles for ornamental daggers.
Authorities in Assam earlier deployed lightly armed forest guards in Kaziranga who were unable to stop the poaching.
