Zoltán Imre Ödön Halmay de Erdőtelek (1881–1956) was a Hungarian Olympic swimmer. He competed in four Olympics (1900 – 1908), winning the following medals: *1900: silver (200 m, 4000 m freestyle), bronze (1000 m freestyle) *1904: gold (50yd, 100yd freestyle) *1906: gold (4×250 m freestyle relay), silver (100 m freestyle) (these games are now not officially recognized by the IOC) *1908: silver (100 m freestyle; 4 × 200 m freestyle relay)
*1900: silver (200 m, 4000 m freestyle), bronze (1000 m freestyle)
*1904: gold (50yd, 100yd freestyle)
*1906: gold (4×250 m freestyle relay), silver (100 m freestyle) (these games are now not officially recognized by the IOC)
*1908: silver (100 m freestyle; 4 × 200 m freestyle relay)