Lorenzo di Pietro (1410 – June 6, 1480), known as Vecchietta, was an Italian Sienese School painter, sculptor, goldsmith, and architect of the Renaissance. He is among the artists profiled in Vasari's Le Vite delle più eccellenti pittori, scultori, ed architettori.
It is believed Vecchietta was a pupil of Sassetta, Taddeo di Bartolo, and Jacopo della Quercia. Later in his life he was the master of Francesco di Giorgio and Neroccio de’ Landi.