Grand Duchess Anastasia Nikolaevna of Russia (Russian: Анастасия Николаевна; 18 June [O.S. 5 June] 1901 – 17 July 1918) was the youngest daughter of Tsar Nicholas II, the last sovereign of Imperial Russia, and his wife, Tsarina Alexandra Feodorovna.

Anastasia was the younger sister of Grand Duchesses Olga, Tatiana, and Maria (commonly known together as the OTMA sisters) and was the elder sister of Alexei Nikolaevich, Tsarevich of Russia. She was murdered with her family by a group of Bolsheviks in Yekaterinburg on 17 July 1918.

Persistent rumors of her possible escape circulated after her death, fueled by the fact that the location of her burial was unknown during the decades of communist rule. The abandoned mine serving as a mass grave near Yekaterinburg which held the acidified remains of the Tsar, his wife, and three of their daughters was revealed in 1991. These remains were put to rest at Peter and Paul Fortress in 1998. The bodies of Alexei and the remaining daughter—either Anastasia or her older sister Maria—were discovered in 2007. Her purported survival has been conclusively disproven. Scientific analysis including DNA testing confirmed that the remains are those of the imperial family, showing that Anastasia was killed alongside her family.

Several women falsely claimed to have been Anastasia; the best known impostor was Anna Anderson.

The abdicated Russian Imperial Romanov family (Tsar Nicholas II of Russia, his wife Alexandra Feodorovna, and their five children: Olga, Tatiana, Maria, Anastasia, and Alexei) were shot and bayoneted to death by Bolshevik revolutionaries under Yakov Yurovsky on the orders of the Ural Regional Soviet in Yekaterinburg on the night of 16–17 July 1918. Also murdered that night were members of the imperial entourage who had accompanied them: court physician Eugene Botkin; lady-in-waiting Anna Demidova; footman Alexei Trupp; and head cook Ivan Kharitonov. The bodies were taken to the Koptyaki forest, where they were stripped, mutilated with grenades and acid to prevent identification, and buried.

Following the February Revolution in 1917, the Romanovs and their servants had been imprisoned in the Alexander Palace before being moved to Tobolsk, Siberia, in the aftermath of the October Revolution. They were next moved to a house in Yekaterinburg, near the Ural Mountains, before their execution in July 1918. The Bolsheviks initially announced only Nicholas's death. For the next eight years, the Soviet leadership maintained a systematic web of disinformation regarding his family, making claims ranging from murder by left-wing revolutionaries in September 1919, to outright denial of their deaths in April 1922.

In 1926 the Soviet regime acknowledged the murders of the entire family (following a French republishing of a 1919 investigation by a White émigré) but claimed the bodies were destroyed and that Lenin's Cabinet was not responsible. The Soviet cover-up of the murders fuelled rumors of survivors. Various Romanov impostors claimed to be members of the Romanov family, which drew media attention away from activities of Soviet Russia.