Preah Khan (Khmer: ប្រាសាទព្រះខ័ន; "Royal Sword") is a temple at Angkor, Cambodia, built in the 12th century for King Jayavarman VII to honor his father.

Like the nearby Ta Prohm, Preah Khan has been left largely unrestored, with numerous trees and other vegetation growing among the ruins.

Preah Khan was built on the site of Jayavarman VII's victory over the invading Chams in 1191 [citation needed].

430 other deities also had shrines on the site, each of which received an allotment of food, clothing, perfume and even mosquito nets;[3] the wealth and treasure of this ruin includes gold, silver, gems, 112,300 pearls and a cow with gilded horns.

[4] The institution combined the roles of city, temple and Buddhist university: there were 97,840 attendants and servants, including 1000 dancers[5] and 1000 teachers.

Clearing works were undertaken with a constant respect for the large trees which give the composition a pleasing presentation without constituting any immediate danger.

At the same time, some partial anastylosis has revived various buildings found in a sufficient state of preservation and presenting some special interest in their architecture or decoration.

It has continued the cautious approach to restoration, believing that to go further would involve too much guesswork, and prefers to respect the ruined nature of the temple.

Each entrance has a causeway over the moat with nāga-carrying devas and asuras similar to those at Angkor Thom; Glaize considered this an indication that the city element of Preah Khan was more significant than those of Ta Prohm or Banteay Kdei.

[10] Halfway along the path leading to the third enclosure, on the north side, is a House of Fire (or Dharmasala) similar to Ta Prohm's.

Between the southern two towers were two celebrated silk-cotton trees, of which Glaize wrote, "resting on the vault itself of the gallery, [they] frame its openings and brace the stones in substitute for pillars in a caprice of nature that is as fantastic as it is perilous.

[12] On the far side of the temple, the third western gopura has pediments of a chess game and the Battle of Lanka, and two guardian dvarapalas to the west.