The dismissed advisers included Salahauddin Sallu, Shakeel Sheikh and Izad Syed. Sallu had been posted in Karachi for the past 5 years.
The development comes days after former International Cricket Council (ICC) chairman Ehsan Mani was elected as the new PCB chairman.
Mani replaced Sethi who resigned from his post as PCB chairman on August 20.
On Thursday, former fast bowler Shoaib Akhtar had tendered his resignation as adviser to the former PCB chairman.
The former star cricketer was appointed as the adviser to former PCB chairman Najam Sethi in February this year.