The article is devoted to the history of the Leningrad archives during the Great Patriotic War and the blockade. The evacuation of the most valuable archival funds and parts of the funds largely repeated the experience of the 1917 evacuation. Especially valuable documents and the collections of finding aids of the archives were evacuated. That allowed to save the most valuable part of the archives, but made it almost impossible to use of information from the archives left in the besieged city. But thanks to the highest professionalism and dedication of the Leningrad archivists, these documents were nevertheless shown up and used in the interests of the defense, foreign policy, the national economy, as well as propaganda. In the most difficult conditions of the blockade, thematic requests were carried out, reviews, lists of documents were compiled, documentary collections were prepared for publication. Social and legal requests were also carried out in the interests of individuals. Documents of “operationalchekist” interest were identified. Work on the use of information from the archives of besieged Leningrad was carried out on a large scale. The archives suffered from bombing and artillery shelling. The greatest losses were suffered by the Central State Historical Archives in Leningrad (TsGIAL). Those losses (as well as losses during evacuation and re-evacuation) amounted to approx 1.3% of the total number of documents stored in the archive. But the main part of the documents of the Leningrad archives was saved.