PCB spokesman Nadeem Sarwar says it received Afridi's reply to the charge following his recent criticism of the board leadership.
Sarwar also says Afridi "is ready to face any disciplinary action against him."
The PCB suspended Afridi's central contract and revoked all of his no objection certificates, which allow him to play overseas.
Apparently, Afridi has pleaded guilty within a day of the PCB's moves in hope of having the NOCs restored so he can play for Hampshire in the English Twenty20 championship.