Implementations of a hair cap are provided. In some implementations, a hair cap may be used to protect the hair of a wearer while they sleep and/or shower. In some implementations, a hair cap comprises a head portion, a pocket portion, and an opening. In some implementations, there may be an elastic band located about the periphery of the opening. In this way, the material about the opening of the head portion may be pulled against a wearer's scalp to potentially prevent water or other liquids from entering the interior of the hair cap. In some implementations, a fastener may be provided on the head portion and another fastener on the pocket portion of a hair cap. In this way the distal end of the pocket portion may be attached to the head portion thereby holding a wearer's hair off of their shoulders and back. In some implementations, silk may be used to manufacture the hair cap. In this way, the wearer's hair is protected from breakage.