Vinod Khanna was originally approached for the lead role, but turned it down because he didn't want to antagonize Rajesh Khanna by co-starring with Dimple Kapadia in the film.
The theme music of Julie, was made into a song in Kaash, "O Yaara". It is said the story of Kaash has been based on filmmakers duo Aruna and Vikas. Actor Mehmood played "jinn" in the film and Mehmood and Mahesh Bhatt worked together for the first time. Mehmood also sang a song in this film for Rajesh Roshan. Mehmood gave a break to Rajesh Roshan in Kunwara Baap. So when Mehmood entered the recording room after many years he was suprised to see the changes in the recording room. Anwar Ali, Mehmood's brother, and F. K. Ratonsy, were the producers of Kaash also they had produced the 1980s Amitabh Bachchan starrer Khud-daar. After Kaash the same producers with Mahesh Bhatt were to make another film Karzdaar with Vinod Khanna, Sanjay Dutt and Jackie Shroff, but then the film was shelved.
It was alleged that Dimple Kapadia got involved with Jackie Shroff during the making of the film. The story went that Sunny Deol and Dimple Kapadia were going through a rough patch in their relationship and Dimple had a fling with Jackie during this period. Both denied the story in print.
Many speculated that Jackie Shroff's role was based on Rajesh Khanna and his career and marriage.
Anupam Kher heavily criticized Mahesh Bhatt over the film. He stated that Mahesh made too many compromises in the film . It was not hard hitting enough. He did not show Dimple's character sleeping with another man. It was the distributors who pressured Mahesh to make the film more family friendly. But Mahesh's real audience and fans wanted something hard hitting like Arth.