Marcelo Omar Garraffo Biano (born September 5, 1957) is a retired field hockey player from Argentina who competed in three Summer Olympics for his native country.

As a coach, he guided the men's national team to the silver medal at the 1999 Pan American Games.

At the end of 2012, he was chosen as the new coach of Argentina women's national field hockey team after Carlos Retegui's contract was not renewed.

Four months later, by decision of the newly elected president of the Argentine Hockey Confederation, Federal Senator Aníbal Fernández, he was dismissed and replaced by Emanuel Roggero.

This biographical article relating to an Argentine field hockey figure is a stub.