Official have reported that 18 militants were killed in southern Sindh province, where the Sufi shrine is located, and another 13 in the north-west.
A suicide bomber blew himself up among devotees at the Sufi shrine in the town of Sehwan, 250 people were also wounded.
So-called Islamic State said it had carried out the attack.
Funeral for victims are taking place on Friday and the Sindh provincial government has announced three days of mourning.