Although Sanjeev Kumar played the father, he was actually several months younger than Shashi Kapoor, who played his son.
Shashi Kapoor calls Rakhee as computer in the film whereas computer was an unheard word in India at that time as America was only familiar with it.
Amitabh Bachchan was nominated for Filmfare best actor award but he lost out to himself for Don 1978.
Poonam Dhillon had disclosed in Big Boss season 3 to the show host Amitabh Bachchan that in a scene from Trishul when she meets with accident Amitabh Bachchan takes her in his arms and drops her home in his car in those days her friends use to ask her how it is to be in Amitabh Bachchan's arms.
Sachin and Poonam Dhillon had a romantic song between them Gapoochi Gapoochi Gam Gam which was big hit at that time.
Gita Siddarth who played Sanjeev Kumar's daughter in law in Sholay 1975 plays his wife in the film.
Mithun Chakraborthy use to frequent a famous tailor shop in Mumbai called "Playboy". Once in 1976, Mithun had arrived at the shop and saw Salim Khan. Salim noticed Mithun standing around and kept observing him. Salim was taken back by Mithun's face. Salim finally approached Mithun and said "Bhai tumhare chehre mein koi kashish hain. Aap filmo mein kyon nahin try karte?". Mithun knew exactly who Salim Khan was and could not believe his ears when Salim Khan paid him that compliment. Mithun told Salim Khan he just graduated from Pune's FTII acting school and was looking for work. Salim Khan gave him Yash Chopra'a address and told him they were casting for Trishul. The needed a boy for the role opposite Poonam Dhillon. Mithun thanked Salim Khan for the help and set out to meet Yash Chopra. Unfortunately Chopra had already signed Sachin for the role.
Three legends Kishore Kumar, Lata Mangeshkar & K. J. Yesudas came together only once for the song Mohabbat Bade Kaam Ki Cheez Hai.
Hema Malini in this film had a small but good important role and she looked very beatiful in this film. This was the second time Yash Chopra and Hema Malini working together, the first was Joshila. Gulshan Rai, Yash Chopra, Rakhee and Hema Malini, all worked toghether in Joshila & Trishul.
The movie was a "Super Hit" at the box office and one of the top grosser of 1978, along with Muqaddar Ka Sikandar and Don.
The scene where Amitabh Bachchan's mother Waheeda Rehman passes away was shown in the film Raja Babu 1994 when Govinda and Shakti Kapoor go to watch Trishul.
While Director Yash Chopra, and Actors Amitabh Bachchan, Hema Malini were in Trishul, 26 years later their sons & daughters - Abhishek Bachchan (Amitabh), Uday Chopra (Yash Chopra), and Eesha Deol (Hema Malini) starred in Dhoom 2004.
Hema Malini was paired opposite Shashi Kapoor but her role was just like special appearance.
Trishul was the last film Yash Chopra, had. directed. for. the producer Gulshan Rai, Trimurti Films.
Rishi Kapoor was offered Sachin's role but he refused which shocked Salim Javed who told him that it will ruin his career if he refuses their film as there were a big name as writers This Rishi mentioned in his autobiography
Raakhee had an unconventional heroine's role in the movie. She had no romantic song with Amitabh.
A separate LP record with the popular dialogue's was released. It was titled "Trishul -The Unforgettable dialogues of Salim Javed.
Rajiv Rai worked as an assistant director.Film was also produced by his father Gulshan Rai under their banner Trimurti Films.Where in Rajiv Rai later directed films under the same banner.
Yash Chopra just gave writers Salim Javed the title as Trishul and asked them to write a script.When the script was complete he saw that there was nothing in the story referring to the title.Salim Javed then told him that it as been titled Trishul as there are three Central characters in the film.
Prem Chopra's character was Balwant Rai.12 years later after this film Amrish Puri's character was called Balwant Rai in Ghayal 1990 which became an iconic character.
Uttar Dakshin 1987 was inspired from this film staring Rajnikanth ,Jackie Shroff and Madhuri Dixit.