Ka, also (alternatively) Sekhen,[2][3] was a Predynastic pharaoh of Upper Egypt belonging to Dynasty 0.

Beyond Abydos, he is attested in the predynastic necropolis of Adaima in Upper Egypt[10] and in the north in Tarkhan, Helwan, Tell Ibrahim Awad, Tell el-Farkha (Eastern Nile Delta), Wadi Tumilat and as far north as Tel Lod in the Southern Levant.

[11] Two underground chambers, B7 and B9, in the Umm el-Qa'ab necropolis of Abydos are believed to be part of the tomb of King Ka.

In the southernmost chamber B7, more than forty inscriptions have been found on tall jars and cylinder vessels as well as a seal impression.

Furthermore, it is located within a sequential order linking the older "U" cemetery with the First Dynasty tombs, thus suggesting that Ka succeeded Iry-Hor and preceded Narmer on the throne.