Puyol had only been in the role for just over three months, but has decided to follow sporting director Andoni Zubizarreta out of the club after the Basque was relieved of his duties earlier on Monday.
"In this statement I want to let you know that I have finalised my working relationship with Futbol Club Barcelona," Puyol wrote on his Facebook account.
"These three and a half months have given me the opportunity to see the other side of the club. I have learned a lot, I am very grateful, but I want to experience other things from another perspective and from other places.
"I want to grow both personally and professionally so that, in future, I can hopefully return to this house and give back everything you have given to me in these unforgettable years."
Puyol also added that he would have preferred to have said farewell on the football field and thanked the fans for their amazing support.
"I am still enormously grateful to the employees, directors, president and the football department for helping and believing in me in this period of transition which has been anything but easy," he said. "But above all, the fans. As a player, I always felt they were very close to me and since my retirement, even more so.
"I would like to have said goodbye to everyone with my boots on, but life doesn't always give you what you wish for. I have been and am extremely fortunate to feel so much affection, and can only say THANK YOU and know that I will always hold you in my heart. Long live Barca!"