Diego Dominguez (born 25 April 1966 in Córdoba, Argentina) is a former rugby union fly-half.

After playing a couple of matches for Argentina, he spent the vast majority of his career with the Italy national rugby union team, winning 74 caps for the latter.

In 1988, Dominguez toured France with the Argentine national team, and in 1989 he scored 27 points in two games for Argentina against Chile and Paraguay.

He is one of only eight players (Dan Carter, Jonny Wilkinson, Ronan O'Gara, Neil Jenkins, Owen Farrell, Johnny Sexton and Florin Vlaicu) in history to have scored more than 1,000 international points.

Stade also reached the final of the Heineken Cup in 2001 but despite Dominguez kicking 30 points, they lost to Leicester Tigers.