Sheirgill started his acting career in 1996 with the critically acclaimed film Maachis, directed by Gulzar, based on the terrorism in Punjab. The film did reasonably well at the box office and got him noticed by all the top filmmakers in the industry, which led him to being cast in Aditya Chopra's Mohabbatein alongside stalwarts like Amitabh Bachchan, Shah Rukh Khan, and Aishwarya Rai. He has consistently won rave reviews for all his performances in films such as Mere Yaar Ki Shaadi Hai (2002), Haasil (2003), Munna Bhai MBBS (2003), Yahaan (2005), Lage Raho Munnabhai (2006), Eklavya: The Royal Guard (2007), A Wednesday (2008), My Name is Khan (2010), Tanu Weds Manu (2011), Saheb, Biwi Aur Gangster (2011), Saheb, Biwi Aur Gangster Returns (2013), Special 26 (2013), Bullett Raja (2013), Fugly (2014) and Tanu Weds Manu Returns (2015). He also worked with rising star of the time Amisha Patel in Yeh Zindagi Ka Safar (2001). He won the Star Guild Awards previously known as Apsara guild awards for Best Actor In A Supporting Role for a movie A Wednesday!