The former Delhi chief minister also applauded the makers and Amir Khan for the performance.
"Just watched PK. Excellent movie. Congrats @aamir_khan for handling such a delicate subject so beautifully," Kejriwal tweeted.
Kejriwal, along with some 25-30 people, which included AAP leaders, watched the movie at a theatre in Sahibabad, party sources said.
In a bid to recapture Delhi, the AAP leader has been undertaking a hectic campaign, with himself addressing over two rallies a day.
The AAP leader is known to have liking for Chinese food.