Marcella Mancini (born 5 September 1971) is an Italian long-distance runner who specialises in the marathon.
A two-time Italian champion in the marathon, she has twice represented Italy at the international level – at the 2005 IAAF World Half Marathon Championships and the 2006 European Championships Marathon.
Her personal best of 2:33:17 hours for the distance was set at the 2005 Turin Marathon.
She is a three-time winner of the Maratona di Sant'Antonio in Padua and won the 2011 Milan City Marathon.
She has also won lower-level races in Reggio Emilia, Ravenna and her home town of Ascoli Piceno.