Julian Reichelt was fired from the Bild tabloid's helm "with immediate effect", the company stated in a statement.
The 41-year old was suspended earlier in the year as part a company-ordered investigation into his management style. He was later reinstated.
Axel Springer stated that it had just received new information on Reichelt from "press investigations". It had also followed up on the investigation, which revealed that Reichelt had "failed" to keep a clear line between professional and private matters even though he was required to after March's internal investigation.
Reichelt also lied about it to the board, according to the company.
Reichelt couldn't be reached for comment.
Axel Springer stated that it would appoint Johannes Boie (37), as the chair of Bild's new three-member editorial board.
After it became known that Reichelt had been the subject of allegations made against him by a rival German media organization, journalists from that group were prevented from publishing their findings.
Four senior journalists from the Ippen media company accused Dirk Ippen and his publisher of a "breach" of trust in a Friday letter. The report had been months in preparation and was scheduled to be published Sunday.
According to Ippen, the media group claimed it had dropped the story to "avoid any impression we might want economic harm to a competitor."
Reichelt was one of the most powerful figures in German media. He was temporarily suspended during the investigation, but was later reinstated by the company after an independent probe found that his actions weren't grounds for dismissal.
Axel Springer stated in a statement that the initial investigation did not include allegations of sexual harassment and assault against Reichelt but instead focused on "consensual intimate relations with female Bild employees" and evidence of power abuse.
The company stated that Reichelt was given a second chance at life.
It stated that "in the context of recent media inquiries, new evidence regarding current misconduct by Julian Reichelt was brought to the company's attention within the last few days."
The company stated that Julian Reichelt, as the executive board learned, still fails to draw a clear line between professional and private matters. He has also been untruthful to this end to the executive boards. The executive board considers it necessary to terminate Reichelt's office.
It also stated that it would take legal action against third parties for disclosing confidential business information or private communications with the intent of trying to harm the company. Reichelt was also removed.
Mathias Doepfner is Axel Springer’s chief executive. He said that Reichelt had done an "exceptional job" at Bild, and that the company would like to continue the development of the media brand "with his onboard."
Doepfner stated that "that is no longer possible." He added that Boie, the new chief editor, "has a proven ability of combining excellent journalism with a leadership style appropriate to today's needs."
Axel Springer's business has grown in the United States over recent years. It is the owner of online media company Insider, as well as the business-oriented Morning Brew. In August, it announced that it had agreed to purchase the U.S.-based political news agency Politico and tech news site Protocol.