The embattled public broadcaster issued the directive in a memo to staff on Thursday, saying "paid appearances can create an adverse impact on the corporation."
The memo says on-air journalists may speak at public events, moderate debates or take part in other public appearances.
But they "must make sure that the activity does not represent any real or perceived conflict of interest" and "get permission from his or her supervisor to do so" beforehand.
The memo was co-signed by CBC News Editor-in-Chief Jennifer McGuire and Michel Cormier, Radio-Canada's executive director of news and current affairs.
It adds that the CBC also plans to "continue to disclose all appearances" on its websites.
"CBC/Radio-Canada holds itself to the highest standards of journalistic integrity. Our standards and practices are among the most rigorous in Canadian media," reads the memo.
"However, a changing environment in which the public expects more transparency from institutions and the media is making the practice of paid outside activities for our journalists less acceptable to audiences."
Last week, the media website Canadaland published a report alleging that the CBC's star business reporter Amanda Lang had tried to "sabotage" a 2013 story on the Royal Bank of Canada.
Canadaland also reported that Lang was in a relationship with an RBC board member and had been paid to speak at public events sponsored by the bank.
The CBC came to Lang's defence and said her paid speaking appearances were approved and did not violate any rules.
Lang also said that she had disclosed her personal relationship to the CBC and denied she did anything to scuttle the story referenced in the Canadaland report.