Lev Vasilevsky was expelled from the Poltava gymnasium "for the organization of a circle of self-education and reading Pisarev and Dobrolyubov". He passed exams as an external student and entered the University of Kiev at the department of the Physics and Mathematics Faculty. He was expelled in 1897 for participating in a demonstration of self-immolation in Peter and Paul Fortress of the people’s leader M.F. Vetrova.
In 1895, in the Poltava Provincial Bulletin I.A. Bunin published two poems by Lev Vasilevsky. In 1902, having graduated from the medical faculty of Kharkov University, he until 1904 worked as a zemstvo doctor in Poltava, Kharkov, and Vladimir provinces. Later Lev Vasilevsky worked as a ship's doctor. As a doctor, he went out to fight epidemics, in 1912 he accompanied I.I. Mechnikov on a trip to the plague-affected regions of the Astrakhan province and to the starving regions of the Urals, Volga Region, and others. In 1914-1916 he worked as a military doctor.
Since 1904, in Saint Petersburg Lev Vasilevsky was engaged mainly in literature, publishing, and social activities. Since 1906 he headed the theater section of the newspaper "Rech", were under various pseudonyms he regularly posted reviews. In 1907 he edited The Free Thought, in 1910 the magazines Iskra, The Sun of Russia, and Morning in Russia. In 1911 Lev Vasilevsky corrected the editorial staff of Studio magazine. In 1917 he corrected the newspaper Petrograd Voice in Helsingfors, worked in local newspapers Russky Vestnik and others.
After the October Revolution, in 1918, Lev Vasilevsky was actively engaged in literary activity in Voronezh. In 1920-1921 he was an employee of the Proletcult in Ufa, simultaneously as a doctor took part in the fight against hunger. After the Civil War, as a result of the concussion, which led to an almost complete loss of hearing, he finished literary activity and was engaged in the dissemination of sanitary and hygienic knowledge.