Giovanna De Grandis (died 5 July 1659, Rome) was an Italian poisoner.
[1] She was one of the central figures of the infamous Spana Prosecution, one of only six to be executed among over forty people to be implicated.
She was working as a laundress when she was recruited to the organization of Gironima Spana, a poison trafficker.
De Grandis was arrested in flagrante on 31 January 1659 and imprisoned in the Papal prison at Tor di Nona, where she was interrogated by the Papal authorities under lieutenant governor Stefano Bracchi.
On 5 July 1659, Gironima Spana, Giovanna De Grandis, Maria Spinola, Graziosa Farina, and Laura Crispoldi were executed by hanging on Campo de' Fiori in Rome.