The following lists events that happened during 1945 in the Union of Soviet Socialist Republics.

• General Secretary of the Communist Party of the Soviet Union — Joseph Stalin
• Chairman of the Presidium of the Supreme Soviet of the Soviet Union — Mikhail Kalinin
• Chairman of the Council of People's Commissars of the Soviet Union — Joseph Stalin

• January 12 — WWII: The Soviet Union begins the Vistula–Oder Offensive in Eastern Europe, against the German Army.^[1]
• January 13 — WWII: The Soviet Union begins the East Prussian Offensive, to eliminate German forces in East Prussia.
• January 17 — WWII: The Soviet Union occupies Warsaw, Poland.
• May 2 — WWII: The Soviet Union captures and occupies Berlin, Germany.
• May 9 — Joseph Stalin declares victory over Nazi Germany during a speech broadcast on radio.
• June 24 — Moscow Victory Parade
• August 9 — WWII: The Soviet Union declared war on Japan shortly after the Atomic bombing of Nagasaki.

• January 3 — Yaroslav Lesiv, Ukrainian poet and priest (d. 1991)
• January 9 — Levon Ter-Petrosyan, 1st President of Armenia
• February 10 — Vladimir Shumeyko, 1st Chairman of the Federation Council of Russia
• February 28 — Alexey Ekimov, Russian solid state physicist
• March 13 — Anatoly Fomenko, Russian mathematician
• March 22 — Givi Gumbaridze, 15th First Secretary of the Georgian Communist Party
• March 26 — Mikhail Voronin, Soviet and Russian gymnast (d. 2004)
• March 28 — Raine Loo, Estonian actress (d. 2020)
• March 31 — Lidiya Belozyorova, Ukrainian actress (d. 2022)
• May 6 — Besarion Gugushvili, 1st Prime Minister of Georgia
• May 14 — Vladislav Ardzinba, 1st President of Abkhazia (d. 2010)
• May 20 — Aleksandr Belyakov, 1st Governor of Leningrad Oblast
• May 22 — Joseph Alliluyev, Russian cardiologist and grandson of Joseph Stalin (d. 2008)
• June 11 — Valery Chaptynov, 1st Head of the Altai Republic (d. 1997)
• June 19 — Natalya Seleznyova, Soviet and Russian theater and film actress
• July 19 — Oleg Fotin, Russian swimmer
• August 4 — Gennady Burbulis, Russian politician (d. 2022)
• August 9 — Zurab Sakandelidze, Georgian basketball player (d. 2004)
• August 14 — Valeriy Shmarov, 3rd Minister of Defence of Ukraine (d. 2018)
• August 29 — Alyosha Abrahamyan, Armenian footballer (d. 2018)
• September 23 — Igor Ivanov, 3rd Minister of Foreign Affairs of Russia
• September 29 — Nadezhda Chizhova, Russian athlete
• October 3 — Viktor Saneyev, Georgian triple jumper, Olympic champion (d. 2022)
• November 5 — Nikolai Tanayev, 8th Prime Minister of Kyrgyzstan (d. 2020)
• November 11 — Gennady Savelyev, 2nd Head of Komi-Permyak Autonomous Okrug
• November 13 — Vladislav Achalov, Soviet and Russian general, politician and public figure (d. 2011)
• December 10 — Yury Yevdokimov, 2nd Governor of Murmansk Oblast
• December 21 — Mari Lill, Estonian actress
• December 24 — Avtandil Margiani, 16th First Secretary of the Georgian Communist Party

• January 6 — Vladimir Vernadsky, mineralogist and geochemist (b. 1863)
• February 18 — Ivan Chernyakhovsky, general (b. 1907)
• February 23 — Aleksey Nikolayevich Tolstoy, writer (b. 1883)
• March 3 — Aleksandra Samusenko, WWII tank commander (b. 1922)
• March 26 — Boris Shaposhnikov, military leader (b. 1882)
• May 7 — Vladimir Boyarsky, army officer (b. 1901)
• May 10 — Aleksandr Shcherbakov, 15th First Secretary of the Moscow City Committee of the Communist Party of the Soviet Union (b. 1901)
• May 25 — Demyan Bedny, poet (b. 1883)
• June 16 — Nikolai Berzarin, Red Army general (b. 1904)
• June 30 — Gabriel El-Registan, poet (b. 1899)
• July 12 — Boris Galerkin, mathematician (b. 1871)
• October 20 — Varvara Massalitinova, stage and film actress (b. 1878)

• 1945 in fine arts of the Soviet Union
• List of Soviet films of 1945