Moisei Uritsky was born into a merchant family in the city of Cherkassy, Kyiv governorate. He graduated from the Law Faculty of Kyiv University (1897). Since 1898, he was a member of the Russian Social Democratic Party (RSDLP). After the 2nd Party Congress (1903), he became a Menshevik. In 1899, he was arrested, in 1901, he was exiled to the Yakutsk governorate. In 1905, Uritsky fled from exile. He took part in the revolution of 1905–1907 in Krasnoyarsk and St. Petersburg. 1906 saw him exiled to Cherkassy. In 1908, he was arrested and exiled to Vologda governorate. He was permitted to travel abroad to be treated for tuberculosis, lived in Germany, Switzerland. In 1910–1912, he was in Russia. In August 1912, Uritsky participated in the Vienna Conference, organized by Leon Trotsky in order to unite Russian Social Democrats. In December 1912, he was arrested in Moscow. In 1913, he was exiled to Arkhangelsk governorate. Due to the exacerbation of tuberculosis, he was again released to be treated abroad. During World War I, he lived in Berlin, Paris, and Stockholm.

After the February Revolution of 1917, he returned to Petrograd. At the 6th Congress of the RSDLP(b) (July to August 1917), together with Mezhraiontsy [an independent group of Social Democrats], he was admitted to the Bolshevik Party, and elected to its Central Committee. Since August 1917, he was a member of the Commission for election to the All-Russian Constituent Assembly. He was elected a glasny [voting deputy] of the Petrograd City Duma (August). A participant of the Democratic conference (September).

Uritsky was also a delegate to the 2nd All-Russian Congress of Soviets, he was elected a member of the All-Russian Central Executive Committee (VTsIK). During the October Revolution of 1917, Uritsky was a member of the Military Revolutionary Center in charge of leading the armed uprising, a member of the Petrograd Military Revolutionary Committee. He was a member of the Collegium of the People’s Commissariat for Foreign Affairs.

Since November 1917, he was Commissar of the All-Russian Commission for Election to the Constituent Assembly. At the end of January 1918, during Felix Dzerzhinsky’s trip to Finland to investigate the circumstances of the attempted assassination of Vladimir Lenin, he acted as Chairman of the All-Russian Extraordinary Commission for Combating Counter-Revolution and Sabotage (VChK). In February 1918, Uritsky headed the headquarters of the Committee for Revolutionary Defense of Petrograd. The 7th Congress of the Russian Communist Party (Bolsheviks) – RCP(b) (March 1918) elected him a candidate for membership in the Central Committee.

After the relocation of the Council of People’s Commissars and the VChK to Moscow, he headed the Petrograd Extraordinary Commission on March 10, 1918. In April–May and July–August 1918, he simultaneously held the post of Commissar of Internal Affairs of the Council of Commissars of the Union of Communes of the Northern Region. In these posts, he was a principled opponent of the death penalty, mass searches, and the hostage system.

On August 30, 1918, he was killed by Popular-Socialist Leonid Kannegiser, a member of Boris Savinkov – Maximilian Filonenko’s organization, in the vestibule of the People’s Commissariat for Internal Affairs of Petrocommune, which was housed in the General Staff building. Along with the attempt of assassination of Vladimir Lenin in Moscow that occurred on the same day, this murder became a pretext for the start of the Red Terror. On September 1, 1918, he was buried on the Champ de Mars.