Gerald Melzer (born 13 July 1990) is a professional Austrian tennis player. As a qualifier, he reached the semifinals of Munich in 2015. He achieved a career-high singles ranking of world No. 68 in November 2016.
He is the younger brother of top Austrian tennis player Jürgen Melzer (hence his nickname, Mini Melts) and is the son of Rudolf Melzer, an Austrian businessman and mayor of Deutsch-Wagram, and Michaela, a saleswoman.
Gerald Melzer has primarily spent his time on the Futures circuit, while also playing challengers and several doubles events with his brother. He began playing on the tour in 2007, competing in tournaments in Austria as well as Futures tournaments in Africa. He has had more success playing doubles, partnering with his brother to win a challenger in Graz, Austria. Gerald faced his brother, Jürgen, in the first round of the 2015 Wimbledon qualifying tournament, and lost in straight sets. Jürgen described it as the "worst tennis day of my life and I hope we will never play each other again."