The EGM also decided to appoint Tomasz Bardzilowski as the new CEO.
Bardzilowski is a managing director at Polish finance company Ipopema Securities, where he also works as an advisor to the firm's board.
The sacking of Dietl, who has been in role since late 2017, comes after a new government pledged to purge state-controlled companies of people it considers political nominees of the ex-ruling party.
The shareholders also voted to make changes to the exchange's supervisory board, voting to appoint, among others, State Treasury's candidates Piotr Prazmo, Jerzy Kalinowski, Iwona Sroka, Katarzyna Szwarc, and Pawel Hominski.
Under the country's law, changes in the exchange's management board have to be approved by Polish Financial Authority KNF to be enforced.
(Reporting by Mateusz Rabiega; Editing by Louise Heavens and David Evans)
