Anna Karenina is a novel by the Russian author Leo Tolstoy, first published in book form in 1878. Considered to be one of the greatest works of literature ever written, Tolstoy himself called it his first true novel. It was initially released in serial installments from 1875 to 1877, all but the last part appearing in the periodical The Russian Messenger. When William Faulkner was asked to list what he thought were the three greatest novels, he replied: "Anna Karenina, Anna Karenina, and Anna Karenina".

The novel deals with themes of betrayal, faith, family, marriage, Imperial Russian society, desire, and the differences. Trains are a motif throughout the novel, with several major plot points taking place either on passenger trains or at stations in Saint Petersburg or elsewhere in Russia. The story takes place against the backdrop of the liberal reforms initiated by Emperor Alexander II of Russia and the rapid societal transformations that followed. The novel has been adapted into various media including theater, opera, film, television, ballet, figure skating, and radio drama.