Paolo Pizzetti (July 24, 1860 – April 14, 1918) was an Italian geodesist, astronomer, geophysicist and mathematician. He studied engineering in Rome, graduating in 1880. He remained in Rome and assisted Giuseppe Pisati and Enrico Pucci with their absolute determination of gravity. In 1886, he became Associate Professor of Geodesy at the University of Genoa where he stayed until becoming Professor of Geodesy at the University of Pisa in 1900. He stayed in Pisa until his death in 1918.