The action comedy film directed by Rohit Shetty also stars Deepika Padukone.
"There is no doubt that Chennai Express has become the biggest box office hit from India since the government allowed screening of Indian movies in the country," Mohammad Qadri the media spokesman for IMGC told PTI.
IMGC is the biggest distribution company in Pakistan with its offices based in Lahore and it imports Indian films via Dubai.
Qadri said that since its release in just eight screens in Karachi, Chennai Express had grossed over 40 million rupees and the figure was mounting.
"I can't give the exact figures now but the initial estimate of ticket sales for the week since its release Chennai Express has grossed over 40 million rupees. The figure will be higher when the final figures of ticket sales for all over Pakistan are available by Monday," Qadri said.
The previous record for highest grossing movie from India was held by Salman Khan's "Dabangg" in Karachi.
Qadri said due to the high demand for tickets the cinema owners had also hiked up prices for Chennai Express and in some areas it was being screened in five to six shows in a day.
"Clearly the Pakistani people enjoy the movies of Shah Rukh Khan and its ticket sales exceeded expectations and it did much better than all the other Eid releases including some Pakistani movies and the Hollywood blockbuster, 'Wolverine'."
Pakistani film critics have also described the film as an entertaining time pass and one critic wrote, "The Shah Rukh Khan and Deepika Padukone starrer is an aesthetically selected evolution of the Dabangg genre."