Harilaos Perpessas (Greek: ?a???a?? ?e?p?ssa?) (born Leipzig, 10 May 1907; died Sharon, Mass., 19 October 1995) was a Greek composer of the Postmodern Era.
He studied mainly with Arnold Schoenberg in Berlin.
There he met Nikos Skalkottas but he remained opposed to both composers' compositional methods.
After his first arrival in Greece in 1934 he became more actively involved in composition.
He often kept revising his works withholding them from publication.