Gujri Mahal is the name of the palace built by Firoz Shah Tughlaq for his mistress Gujri. The palace is located outside the fort complex to east and was built as an outlying portion of it. Between the Gurjari mahal and the main fort complex there existed a now-vanished Islamic garden, which is now the location of modern-day Jindal park with a 207 feet tall Flag of India.

Gujri was the mistress of Firoz Shah Tughlaq. She was a local resident of Hisar. When he asked her to accompany him to the throne at Delhi, she refused. So, he built a palace for her in Hisar (city) and built his own palace complex around it.

The palace was built using rubble and Mortar. Like other structures present inside the complex, this was also built using parts of destroyed temples as is visible from the pillars located inside the palace.

Only a small portion of the two-story palace with one underground level remains now. The palace is built on a rectangular platform that can be approached by a ramp leading to the upper level. The building has been declared as a Centrally Protected Monument by Archaeological Survey of India. The palace is closed for public. To the north, there used to be gardens, which no longer exist and houses modern have been built there.

The most visible part of the what now remains of the palace is the Baradari on the upper level, called so because of the presence of twelve doorways, three on each side. It was used for social gatherings. Four Hindu pillars are located inside the chamber to support the roof. These pillars were taken from the destroyed Hindu and Jain temples, most likely from Agroha Mound or nearby area.

There are three underground apartments located below the platform. One of them is a tank and it is believed that this tank served as a hammam or bath.

On the upper level, there are a total of nine graves, 5 of which are sarcophagi on an open-air higher platform (nearly 3 feet from bottom), two are sarcophagi on a separate nearby open-air lower platform (less than 1 foot from bottom) and two are brick shrines inside a brick structure that no longer has a roof. Total seven of them are sarcophagi while the other two are brick shrines. All of them belong to 17th or 18th century Mughal empire era.