Iakov Feigin was born in 1903 in the area of Chernigov, Ukraine. In 1931, he graduated from the Second Moscow State University. From 1932 to 1941, he worked at the Institute of Economy at the Academy of Sciences of the USSR and was awarded the rank of professor. In 1940 he co-authored the textbook Economical Geography of the USSR and in 1941 he published the monograph The Spatial Distribution of Productive Forces in the USSR.
In July 1941, Feigin was drafted into the Red Army. He began serving as the commander of an artillery platoon and was later promoted to be the commander of a company. According to some accounts, Feigin learned about artillery directly from field experience. In February 1941, he was transferred to an artillery regiment headed by the Jewish general Grigorii Plaskov, in the capacity of political commissar of the regiment. In 1943, Major Feigin was promoted to be deputy commander for political matters of the 10th Artillery Brigade.
Despite be formally a political worker, a number of times Feigin participated in field operations as a commander of his unit. For such actions, he was awarded the Orders of the Red Star and the Order of the Red Banner, as well as receiving other military honors. In May 1942, during the Red Army's retreat in southern Russia, when his regiment was unloading cannons from a train, the commander of the regiment was seriously injured. Commissar Feigin assumed command and, under severe enemy bombing, supervised the unloading without the loss of materiel or ammunition. For this, he was awarded the Order of the Red Star.
In the spring of 1942, due to his high level of education, Feigin was offered the position of lecturer at a military academy in Moscow. Feigin refused the offer since he considered it his duty to be on the front lines.
He received the Order of the Red Banner in April 1945, during the battle of Berlin.
After the war, Feigin was the director of the Institute of Economics of Ukraine and a corresponding member of the Ukrainian Academy of Sciences. He died in 1973.