After appearing as a child artist in Dharam Veer (1977), Deol had his first lead role in the romance Barsaat (1995), which won him the Filmfare Award for Best Male Debut.

[10] Deol made his acting debut as an adult alongside Twinkle Khanna in Rajkumar Santoshi's 1995 romance film Barsaat, where he played a naive but intelligent young man who moves from a small village to the big city and gets caught up with corrupt police and criminal gangs amidst falling in love.

[12] He replicated this success with his next starring role in Rajiv Rai's suspense thriller Gupt: The Hidden Truth (1997) alongside Manisha Koirala and Kajol, as a man accused of murdering his stepfather over an engagement proposal and wrongly imprisoned.

He teamed up with Abbas–Mustan for the first of many collaborations in the military thriller Soldier (1998), co-starring Raakhee and Preity Zinta, in which played the son of a man who was convicted of arms smuggling.

In Badal, set around the 1984 riots in engulfing parts of Punjab and Delhi, his character witnesses the massacre of his family and villagers by a corrupt inspector and grows up to be a dreaded terrorist.

[18] In Bichhoo, Deol's role as a young middle-class guy who falls in love with a wealthy woman was panned although the film hailed good box-office returns.

Deol next essayed a married guy entangled in a web of deceit and extra-marital affairs, in Abbas–Mustan's thriller Ajnabee (2001) alongside Kareena Kapoor, Akshay Kumar and Bipasha Basu.

He reunited with Sunny Deol for the failed historical drama 23rd March 1931: Shaheed (2002), where he and his brother portrayed the roles of freedom fighters Bhagat Singh and Chandra Shekhar Azad respectively.

"[22] Later in 2002, Deol was nominated for the Filmfare Award for Best Actor for his role as a suave, wealthy shipping businessman in Abbas-Mustan's romantic thriller Humraaz, where he was involved in a love triangle with Ameesha Patel and Akshaye Khanna.

[23][24] The film was moderately successful but received positive reviews from critics,[23][25] with Chitra Mahesh of The Hindu saying, "Deol spends the entire first half looking moony eyed and spaced out, but overcomes the stupor towards the end where he actually gives a good performance.

"[25] His final act in 2002 was of a small-time crook who gets his hands on some diamonds worth millions, in David Dhawan's Chor Machaaye Shor alongside Shilpa Shetty, Bipasha Basu, Paresh Rawal and Om Puri.

While the former dealt with themes of police brutality and corruption and justice, the latter was an ensemble film starring Amitabh Bachchan, Akshay Kumar and Deol (in a double role).

Deol reteamed with Vikram Bhatt for the thriller Jurm (2005), hailing praise for his role as a wealthy businessman who suspects his wife of having an affair with Rohit.

"[29] He was equally unimpressed with Deol's performance, remarking, "The girls are ready with their curls and curves, the guy just appears lost, making you wonder if Bobby has grown even an inch as an actor since he made his debut in Rajkumar Santoshi's film of the same name.

"[29] His final role of 2005 was Dosti: Friends Forever with Akshay Kumar, Lara Dutta, Kareena Kapoor and Juhi Chawla, which underperformed in India but was a major success in the United Kingdom.

[30] In 2006, Deol reunited with Ameesha Patel in the romantic musical film Humko Tumse Pyaar Hai, where his characters falls in love with a beautiful blind woman who has a talent for shaping pottery.

For instance, Raja Sen of Rediff.com praised several of his scenes, remarking, "Bobby gets a considerably meaty role, and there are a couple of moments when he genuinely works the audience", but describes his character as "sensitive to an annoying hilt".

In 2008, Deol starred as an orphan raised by a Naxal leader opposite Priyanka Chopra, Danny Denzongpa and Irrfan Khan in Kabeer Kaushik's crime drama Chamku, set in the interiors of Bihar.

[39] He worked in another failed ensemble film Heroes (2008) as an army officer with Salman Khan, Preity Zinta, Sunny Deol and Mithun Chakraborty.

And suddenly I heard my son saying ‘Mom, papa sits at home and you go to work everyday.’ And then something snapped in me and I said ‘No, I can’t do this anymore’.”[49]Following the hiatus, he tried to make a comeback with Shreyas Talpade's Poster Boys (2017) alongside Sunny Deol.

[68][69] In 2024, Deol played a negative role opposite Suriya in the Tamil period action drama Kanguva, which ranks amongst the most expensive Indian films.