The Swedish international has branded the Spaniard a "spineless coward" and has said that his time at Camp Nou was like being back at school.
"I'd already got the impression that Barcelona was a little like being back at school," he wrote in his autobiography I am Zlatan Ibrahimovic.
"None of the lads acted like superstars, which was strange. [Lionel] Messi, Xavi, [Andreas] Iniesta, the whole gang - they were like schoolboys. The best footballers in the world stood there with their heads bowed and I didn't understand any of it.
"It was ridiculous. Everyone did as they were told. I didn't fit in, not at all. I thought, just enjoy the opportunity, don't confirm their prejudices."
Ibrahimovic describes an incident in which he and Guardiola clashed following Barca's defeat to Inter Milan in the Champions League.
"I completely lost it," Ibrahimovic wrote. "You might have expected Guardiola to say a few words in response, but he's a spineless coward."
Ibrahimovic recently pledged his future to PSG following reports linking him with a return to Italy.