Naya Mandir (नया मंदिर, literally: new temple) or Harsukhrai Mandir is a historic Jain temple in Old Delhi, in the Dharampura locality allocated to the Jain community by Aurangzeb.
Raja Harsukh Rai, imperial treasurer in the late Mughal period, constructed a large and ornate Jain temple in the Dharampura locality of Old Delhi in 1807 during the rule of Mughal Emperor Akbar II with a cost of about 8 Lakh rupees, then an enormous amount. He was able to obtain the royal permission to construct a shikhara for the temple for the first time during the Mughal rule. Thus temple is known as the Naya Mandir (new temple), since an older Jain temple, now known as the Lal Mandir already existed.
When the temple construction was almost finished, Harsukh Rai stopped the construction. When the representatives of the Agrawal Jain community approached him and asked about it, he claimed that he has run out of money and needed donations from the community to finish the construction. After accepting modest donations, Harsukh Rai declared the temple to be panchayati (i.e. belonging to the community, rather than himself) and finished the construction.
During the festivities of temple consecration (Panch-kalyanak Pratishtha), the festive pandal was raided by a local group and the gold and silver objects (chhatra, chamar, utensils) were plundered. Harsukh Rai complained to the Emperor, who ordered that they be returned.
The temple houses an important collection of manuscripts.