Horwennefer, also known as Hurganophor or Haronnophris, was an Egyptian who led Upper Egypt in secession from the rule of Ptolemy IV Philopator in 205 BC. Along with his successor, Ankhwennefer, they held a large part of Egypt until 186 BC. No monuments are attested to this king, but a graffito dating to about 201 BC on a wall of the mortuary Temple of Seti I at Abydos, in which his name is written Ὑργοναφορ, is an attestation to the extent of his influence and the ideology of his reign. He appears to have died before 197 BC.