Both Salman and Ajay will be competing with each other for the best actor trophy and both the films have also been nominated in the best film category.
Other actors fighting for the title of best actor are Hrithik Roshan for "Guzaarish", Shah Rukh Khan for "My Name Is Khan" and Ranbir Kapoor for "Rajneeti".
The best film category also includes "Band Baaja Baaraat", "My Name Is Khan" and "Rajneeti".
"Once Upon A Time in Mumbaai" has also been nominated for best direction by Milan Luthria. Emraan Hashmi has picked up two nominations for best actor in a supporting role and best performance in a negative role, while Prachi Desai has been nominated for best actress in a supporting role for the film.
Other nominations include best music for Pritam, best lyrics Irshad Kamil for the song "Pee loon", best screenplay, best dialogue and best story for Rajat Arora and Mohit Chauhan as best playback singer male for "Pee loon".
"Dabangg" has also been nominated in best direction category for Abhinav Kashyap, best supporting actress for Dimple Kapadia and best performance in a negative role for Sonu Sood. Dilip Shukla and Abhinav Kashyap have been nominated in best screenplay as well as best dialogue categories.
Music composers Sajid-Wajid and Lalit Pandit have been nominated in the best music category, while Rahat Fateh Ali Khan (Tere Mast Mast Do Nain) and Mamta Sharma (Munni Badnam) have landed nominations in best playback singer male and best play back singer female categories respectively. Faiz Anwar has been nominated in the best lyrics category for "Tere mast mast do nain".
Newcomer Anushka Sharma will be competing with established actresses like Kareena Kapoor for "Golmaal 3", Aishwarya Rai Bachchan for "Guzaarish", Vidya Balan for "Ishqiya" and Katrina Kaif for "Rajneeti".
The nominations in best direction category are Maneesh Sharma for "Band Baaja Baaraat", Sanjay Leela Bhansali for "Guzaarish", Karan Johar for "My Name Is Khan" and Vikramaditya Motwane for "Udaan".
The nominations in best actor in a supporting role are Mithun Chakraborty for "Golmaal 3", Arshad Warsi for "Ishqiya", Arjun Rampal and Manoj Bajpayee for "Rajneeti", while the best supporting actress category include Amrita Puri for "Aisha", Ratna Pathak Shah for "Golmaal 3", Shernaz Patel for "Guzaarish".
Best actor in comic role nominations are Paresh Rawal for "Atithi Tum Kab Jaoge", Johnny Lever for "Golmaal 3", Ritiesh Deshmukh for "Housefull", Anil Kapoor for "No Problem" and Praduman Singh for "Tere Bin Laden".
The nominations for best music director are Salim-Suleman for "Band Baaja Baaraat", Vishal-Shekhar for "I Hate Luv Storys", Vishal Bhardwaj for "Ishqiya" and "Shankar Ehsaan Loy" for "My Name is Khan".
Best playback singer male nominees are Vishal Dadlani for "Adhoore" from "Break Ke Baad", Shafqat Amanat Ali for "Bin tere" from "I Hate Luv Storys", Rahat Fateh Ali Khan for "Dil toh bachcha hai ji" from "Ishqiya" and Shankar Mahadevan for "Uff teri ada" from "Karthik Calling Karthik".
Those competing in the best playback singer female category are Sunidhi Chauhan for "Ainvayi Ainvayi" from "Band Baaja Baaraat" and "Shiela ki jawani" from "Tees Maar Khan", Shreya Ghoshal for "Bahara" from "I Hate Luv Storys" and Rekha Bhardwaj for "Ab muzhe' from "Ishqiya".
The awards will be held in Toronto from June 23-25.