Patricio Loustau (born 1975) is an Argentine football referee.
He was selected to referee 2014 FIFA World Cup qualifiers. On September 6, 2013, after officiating the 2-1 victory for Uruguay over Peru in a qualifier at the Estadio Nacional of Perú, he had to be escorted out of the stadium due to angry Peruvian fans, who were upset over controversial calls in the match. Peruvian press claimed he was following CONMEBOL instructions, especially from the newly appointed CONMEBOL President Eugenio Figueredo, who is an Uruguayan national.
Loustau was selected as one of the referees for Copa America Centenario where he officiated the Paraguay vs. Costa Rica Group A match in Orlando, Florida.
His father, Juan Carlos Loustau, is a retired football referee.