Ptghni (Armenian: Պտղնի, also Romanized as Ptykhni, Ptgni, and Ptkhni) is a village located in the Kotayk Province of Armenia along the left bank of the Hrazdan River. It was founded in 1831 in the vicinity of an abandoned dwelling. The village has a house of culture, school, kindergarten, and a library. Local inhabitants predominantly grow grapes, melons, gourds, and breed cattle.
Within the village are the remains of fortress walls and Ptghavank of the 6th to 7th century.