Alex Callier (born 6 December 1972, in Sint-Niklaas, Belgium) is a member of Belgian Rock band Hooverphonic. He studied sound engineering in the Rits school in Brussels and attended several music classes in both his hometown, Sint Niklaas, and Antwerp. Between 1994 and 1997 he worked as a sound engineer for the Belgian VRT TV channel. There he met Frank Duchêne with whom he started Hoover (later Hooverphonic) in 1995. He is the main programmer/composer and producer for the group and the "main musical force". He started playing keyboard in the band and the bass later. In 2000 he was awarded the ZAMU Award for best Belgian producer for the soundtrack of the film Shades.
He has also been a member of the jury of The Voice van Vlaanderen for several seasons.