This article examines the key Russian strategic and tactical narratives on nuclear security during Russia’s full-scale aggression against Ukraine. Particular attention will be given to Russian claims that Ukraine is developing a “dirty bomb,” that Ukraine is shelling the Zaporizhzhia nuclear power plant, and that the Ukrainian nuclear industry is decaying. The Russian disinformation campaign against the Ukrainian nuclear energy sector is part of a broader Russian strategy of nuclear blackmail against Ukraine and the West.