"He has suffered a lot. If he gets mercy, then nothing like it," Chiranjeevi told reporters here on the sidelines of a tourism-related event.
"He is regretting what he has done. He is a nice person. I pray for him from the bottom of my heart. My sympathies are with him," he added.
Dutt was sentenced to five years in jail by the Supreme Court March 21 for illegal arms possession during the 1993 Mumbai bomb blasts.
He was asked to surrender in four weeks to serve his remaining term of three-and-half years as he has already spent 18 months in jail.
Several members of the film fraternity and politicians like former Samajwadi Party leader Amar Singh and actor-turned-politician Jaya Prada have spoken in Sanjay's support.
Press Council of India chairperson Markandey Katju also sought pardon on humanitarian grounds for the actor and Zaibunissa Kazi, both of whom have been sentenced to five years in prison for their role in the 1993 Mumbai bombings.
However, other political parties like the BJP and the Shiv Sena have opposed the move, saying it would not be fair to pardon Dutt.