The Marshal Shaposhnikov, a large ASW ship, was returning to its home base near Vladivostok after exercises in the Sea of Japan when the fire started in the engine room.
"According to reports from the Pacific Fleet, the fire occurred on the [Admiral Shaposhnikov] ship, killing two seamen who were in the engine room at the time," Capt. 1st Rank Igor Dygalo said.
"It took eight hours to put out the fire," he said.
The warship, which has been towed to port, was part of a naval task group which conducted live firing drills at dummy airborne and surface targets on September 15-17.
The drills were the third in a series of combat training exercises conducted by the Pacific Fleet in the past month. Two previous exercises off Russia's Far East coast involved over 50 warships and submarines, along with naval aircraft and naval infantry.
Dygalo said military prosecutors have launched an investigation into the fire.