Boris Kornilov was born into the family of a village teacher in the Pokrovskoye Settlement of the Nizhny Novgorod province (nowadays Semyonovsk District of the Nizhny Novgorod Region) on July 16, 1907. In 1922 Boris moved to Semyonov and started writing poems.

The first publications of his verses saw the light in 1923.
In 1925 the aspiring poet moved to Leningrad to show his poems to Sergey Yesenin, but it was too late to see the latter alive. Boris Kornilov joined the poetic group Smena (The Shift) under the leadership of V. M. Sayanov, and was soon recognized one of the most talented young poets of Russia.

In 1926 Boris Kornilov with the poetess Olga Berggolts, also a member of The Shift entered the High State Courses of Art Criticism at the Institute of Arts History. Boris and Olga got married and lived together for two years. Their little daughter Ira died of a heart disease in 1936.

The year 1928 saw the first publication of Boris Kornilov's collected poems The Youth. It was followed with the volumes The Book of Verses and Verses and Poems in 1933.

In 1932 the poet wrote about elimination of kulachestvo, and was accused of "furious kulak promotion". Boris Kornilov was partly rehabilitated for Soviet ideologists with his poem Tripolye dedicated to the memory of the Komsomol members killed during a kulak revolt.

In the mid-1930s Boris Kornilov was undergoing a crisis and misused alcohol. He was repeatedly exposed to criticism in newspapers for his "antisocial conducts".

In October, 1936 the poet was expelled from the Union of Soviet Writers. Boris Kornilov was accused of participating in an anti-Soviet plot and arrested in Leningrad on March 19, 1937.

The executed poet was posthumously rehabilitated on January 5, 1957 "for lack of evidence".