Aleksey Nikolayevich Pleshcheyev (Russian: Алексе́й Никола́евич Плеще́ев; 4 December [O.S. 22 November] 1825 – 8 October 1893) was a radical Russian poet of the 19th century, once a member of the Petrashevsky Circle.

Pleshcheyev's first book of poetry, published in 1846, made him famous: "Step forward! Without fear or doubt..." became widely known as "a Russian La Marseillaise" (and was sung as such, using French melody), "Friends' calling..." and "We're brothers by the way we feel..." were also adopted by the mid-1840s' Russian radical youth as revolutionary hymns.

In 1849, as a member of Petrashevsky Circle, Pleshcheyev was arrested, sent (alongside Fyodor Dostoyevsky among others) to Saint Petersburg and spent 8 months in Peter and Paul Fortress. Having initially been given a death sentence, Pleshcheyev was then deported to Uralsk, near Orenburg where he spent ten years in exile, serving first as a soldier, later as a junior officer.

In his latter life, Pleshcheyev became widely known for his numerous translations (mostly from English and French) and also poems for children, some of which are now considered classic. Many of Pleshcheyev's poems have been set to music (by Tchaikovsky and Rachmaninoff among others) to become popular Russian romances.