| Lev Ilyin | |
| Native Name: | Лев Александрович Ильин |
| Native Name Lang: | ru |
| Nationality: | Russian |
| Citizenship: | Soviet, Russian |
| Birth Date: | 25 June 1879 |
| Birth Place: | Moscow, RSFSR |
| Death Place: | Saint Petersburg |
| Alma Mater: | Alexandrovsky Cadet Corps |
| Significant Projects: | City plan of Saint Petersburg |
Lev Aleksandrovich Ilyin (; 1880 in Tambov Governorate, Russian Empire – 1942) was an architect from the Soviet Union.
Between 1925 and 1938 Lev Ilyin was the main architect of Leningrad (now Saint Petersburg), and an author of the overall map of Leningrad and material in the sphere of town-planning. He served as the general director of the Russian State Research and Design Institute of Urbanism.
During the Siege of Leningrad, Ilyin died during a German bombing raid.[1]