The Poland forward, who scored 344 goals for Bayern in 375 games, joined Barca in a deal worth 45 million euros ($46.06 million) last month after forcing a move from the German club.
The 33-year-old and Bayern bosses have criticised each other over the way they handled the transfer, with Lewandowski saying there had been lot of "politics" from the side of the club who were "trying to find an argument" to sell him.
Bayern in turn said the situation had been caused by the player who asked to leave despite having a contract to 2023.
"Everything is fine. I met everyone and thanked them," Lewandowski told Sky television from his car before driving away from the club offices. "I will never forget what I received here and what I experienced.
"That is the most important thing for me," he said. "Last week was a bit complicated but sometimes this is part of football."
Bayern sports director Hasan Salihamidzic spoke with Lewandowski during his brief visit and they cleared the air.
"Robert came into my office to say goodbye and we talked for 15 minutes," he said in a club statement.
"I addressed everything and we cleared everything. Robert did great things for Bayern and that's what should remain. He knows as well what he has to thank Bayern for."
Lewandowski won almost every domestic and international club title with Bayern, including eight league crowns, three German Cups, the Champions League and Club World Cup among others.
He is the Bundesliga's second highest all-time scorer behind the late Gerd Muller.
