The Mail on Sunday has lost a challenge to a High Court judgement on publishing the Prince of Wales's private diaries.
The prince wrote about the handover of Hong Kong to China
Prince Charles had won a ruling that his copyright and confidentiality were infringed when the paper published extracts from his 1997 journal.
The Court of Appeal said publication interfered with his private and family life protected by the Human Rights Act.
The extracts, on the handover of Hong Kong to China, referred to the Chinese hierarchy as "appalling old waxworks".
The Lord Chief Justice, Lord Phillips, dismissing the newspaper's appeal, said: "As heir to the throne, Prince Charles is an important public figure.
"In respect of such persons, the public takes an interest in information about them that is relatively trivial.
"For this reason, public disclosure of such information can be particularly intrusive."
Mark Warby QC, representing the Mail on Sunday, told Lord Phillips, Master of the Rolls Sir Anthony Clarke, and Lord Justice May at a hearing last month that the diary contained important information about the prince's opinions.
However, Lord Phillips said interference with the prince's human rights "outweighed the significance" of interference with the newspaper's right to freedom of expression under the same Act.
Following the ruling, the Prince of Wales's Principal Private Secretary Sir Michael Peat said: "We are pleased that the Court of Appeal has decided that the Prince of Wales's case for breach of confidence is 'overwhelming' and has dismissed the Mail on Sunday's appeal.
"This confirms what we have always maintained, that the Prince of Wales, like anyone else, is entitled to keep his private journals private."
The journal was one of eight handed over to the newspaper by a disaffected former secretary in the prince's office.
In March, High Court judge Mr Justice Blackburne supported the prince in his battle against publication but said a decision on the seven other journals would have to go to a full trial.