The 57-year-old has been under growing pressure following controversies culminating in a newspaper report on Monday that he had accepted the gift of a €6,000 watch from Hryhoriy Surkis, a UEFA vice-president and honorary president of the Ukrainian football federation.
“I am stepping down from the position of DFB president, and I apologize for my less than exemplary behaviour regarding my acceptance of a watch,” said Grindel.
Surkis sat alongside Grindel on the executive committee of European football's governing body UEFA until last February. Yet Grindel denied that he had been given the watch for political reasons.
“For me this was an entirely private gift which I was bound to accept out of politeness,” he said.
“I did not have any idea how expensive the watch was and it was a grave oversight on my part not to find out. In doing so, I could have avoided the impression that I was acting inappropriately.”
Grindel said that Surkis had “no economic interest in the DFB”.
“I am deeply shaken to have to give up my role as DFB president over such an issue,” Grindel said.
“I ask myself: why has this happened? I can only say that I was completely convinced that I was doing nothing wrong and that, in the stress of my position, I did not question myself enough.”
Mesut Özil scandal
A former journalist and member of the German parliament for the centre-right CDU party, Grindel had been president of the DFB since 2015.
In recent months, he oversaw Germany's successful bid to host Euro 2024, but also came under fierce criticism for his handling of various scandals.
He was singled out by Mesut Özil, who accused Grindel of overseeing a culture of institutional racism, when the Arsenal midfielder retired from international duty last July.
“In the eyes of Grindel and his supporters, I am German when we win, but I am an immigrant when we lose,” wrote Özil in his explosive resignation statement.
Grindel has also come under increasing fire from the media in recent weeks.
In March, he broke off an interview with broadcaster Deutsche Welle after refusing to answer questions about the 2022 World Cup in Qatar.
On Friday, magazine Der Spiegel alleged that Grindel had kept quiet about €78,000 of income which he had received from a DFB subsidiary in 2016 and 2017.
The DFB responded with a statement saying that Grindel had declared all his income correctly.
On Tuesday, the association confirmed that vice-presidents Rainer Koch and Reinhard Rauball would take over as joint interim presidents until Grindel's successor is elected.
Bild has already named ex-Germany and Real Madrid defender Christoph Metzelder, 38, as a possible replacement.
Former Bayern Munich player Philipp Lahm has ruled himself out of the running, saying that he had “no interest” in the presidency.
By Kit Holden