Viktor Stelnik was born in 1922 in Kiev. His father Aron was a Soviet functionary who, according to some sources, was a peoples' commissar (minister) of the fish industry of Ukraine before World War II. In 1940, Viktor was drafted into the Red Army, where he served in the artillery.
With the beginning of Operation Barbarossa in June 1941, Stelnik fought on the Southern Front (in southern Ukraine). After three months he was sent to an officers' course. In mid-1942 Lieutenant Stelnik was assigned as commander of a battery in the 167th Regiment of Light Artillery. In the winter of 1942-1943, his regiment took part in the Battle of Stalingrad, for which Stelnik was awarded the Order of the Red Star. Despite being an artillerist, more than once he led his platoon in hand-to-hand, bayonet fighting. During one battle, the hill on which his battery was located was captured by the enemy; by radio Stelnik called on his command to shell his hill. His platoon was hidden in a dugout. After that Stelnik was awarded the Order of the Patriotic War, 1st Class, and was promoted. In 1943 Guards Captain Stelnik became the commander of a battalion.
In July 1943, Viktor Stelnik and his regiment took part in the Kursk Salient operation. On July 27, 1943 he was killed by an enemy shell near the village of Trosna, south of Orel. He was buried in a common grave in the village. His name was engraved on a stone slab that was part of the memorial established after the war at the common grave. He was posthumously awarded his second Order of the Patriotic War (this time, 2nd Class).
An article on Viktor Stelnik was prepared for the Soviet Yiddish newspaper Eynikayt in 1943.