The 46-year-old announced his decision after Wednesday's 6-1 La Liga win over Sporting Gijon which keeps his side in contention for his third championship title.
Manchester City boss Guardiola remains a member at the Nou Camp after a highly successful playing and managerial career with the Catalan giants.
Guardiola, speaking after City's FA Cup fifth-round replay win over Huddersfield, said: 'I have two reactions. As a Barcelona fan, as a supporter, the club of my heart, I am so sad.
'We are going to miss the perfect trainer for his personality, his character. In his three years he played unbelievable football with unbelievable players.
'The second, if he has decided that I understand him completely and of course I wish him the best.
'As a fan, from the membership of Barcelona, I say thank you for all he has done in three years at my club.'
Guardiola, who won the Champions League twice with Barca, recently denied he would be interested returning to the club.
'I will never go back to Barcelona to be coach there,' he said last month. 'My period there is gone.'