The music of the film is composed by Sajid-Wajid, Jeet Gannguli, Gunwant Sen, Sachin Gupta and Babli Huque-Meera while lyrics were written by Abid Ali, Danish Sabri, Sonu Saggu, Sajid Qureshi and Sachin Gupta. The first song of the film, Tere Thumke Sapna Choudhary which is sung by Gunwant Sen, Khushboo Jain and Saumya Upadhyay was released on 21 March 2018. The second single to be released was Bhoot Aaya which is by Mika Singh and rapped by Fazilpuria and was released on 11 April 2018. The soundtrack was released by T-Series on 16 April 2018.

Reza Noorani of The Times of India gave the film a rating of 2.5 out of 5 saying that, "While the story is unique and interesting, the execution is flawed, especially when it comes to the horror elements." Saibal Chatterjee of NDTV gave the film a rating of 1 out of 5 and said that, "The spirits of two much-abused genres - horror and comedy - are given an unceremonious burial in Nanu Ki Jaanu, a heavy-handed jumble that is both horrific and funny, neither of which is remotely intentional." Rohit Vats of Hindustan Times gave the film a rating of 1.5 out of 5 and said that, "Nanu Ki Jaanu is 132-minute of convoluted chaos. Some talented actors are wasted and some are given a free run to waste their talent."^[11] Nandini Ramnath of Scroll gave the film a rating of 1 out of 5 and said that, "Faraz Haider’s remake of the Tamil movie ‘Pisaasu’ works very hard to scare viewers away."^[12] Anna MM Vetticad of First Post criticized the film saying that, "Abhay Deol is uninspired at best in this loosely handled, low-IQ mess" and gave the film a rating of 1 out of 5.^[13]

Bollywood Hungama criticized the film, which is a remake of Tamil film Pisaasu, for being a poor adaptation saying that, "The adaptation by Manu Rishi Chadha is very poor. Manu Rishi Chadha’s screenplay is very weak and only a few moments stand out." The critic concluded the review by saying that, "On the whole, Nanu Ki Jaanu is an extremely poor show." and gave the film a rating of 1.5 out of 5.^[14] Shubhra Gupta of The Indian Express gave the film a rating of 1 out of 5 saying that, "Nanu Ki Jaanu is so all-out scatter-brained and lame, that we are left wincing rather than laughing."^[15] Sameeksha of News18 gave the film a rating of 1.5 out of 5 and concluding her review by saying that, "Overall the film is uneven, half-baked disappointment, which completely wrecks the talent of Abhay, Patralekha and even Chadha. They all deserve better than this."^[16] Mayank Shekhar of Mid-Day gave the film a rating of 1 out of 5 and said that, "Suffice it to say, by the end of Nanu Ki Jaanu, pretty much everyone in my theatre (me included) were essentially laughing at the film, rather than with it".^[17] Namrata Joshi of The Hindu criticized the film saying that, "Not quite supernatural thriller, Abhay Deol’s latest is plain dull."^[18]