The improvised explosive device (IED) exploded when an Assam Rifles team was patrolling Maha Mani of Chandel Town in the district, about 64 km from the state capital.
In a statement emailed to the local media, the banned insurgent outfit Revolutionary Peoples Front (RPF) claimed responsibility for the attack.
One jawan died on the spot, while another succumbed to injuries on the way to hospital, the police said.
The deceased were identified as riflemen Indra Singh and Sohan Lan.
Manipur Governor Najma Heptulla condemned the incident and appealed to those responsible to lay down their arms and join the mainstream.
The outfit had carried out an IED blast on June 15 this year in Ukhrul district that killed an Assam Rifles jawan and injured three others.