The guard, identified as Rampal Saini (42), was on patrol last evening with two others when the tiger mauled him, police said.
His colleagues rushed him to a hospital where he died, they said.
Chief Minister Vasundhara Raje has expressed grief over the death of the forest guard, a release said.
She also directed the MoS for Forest and Environment, Rajkumar Rinwa and concerned officials to visit his family, it added.