Kaziranga National Park (KNP) lost its first rhino this year with poachers killing a male animal at Bagori range of the park on Sunday night.
The carcass with its horn intact was found near Daflang camp in Bagori range of the park.
An official of the park said that the rhino, aged about 30, died of bullet injuries.
The official added that a search operation is on to track down the poachers.
According to official data, Kaziranga has lost over 170 rhinos since 2001. However, poaching dropped in 2017 compared to the period between 2013 and 2016.
As many as 18 rhinos were killed by poachers in 2016 in the national park while the toll of poaching in 2017 was five.