The suspension begins next Monday.
MSNBC, which telecasts the radio show, said Imus' expressions of regret and embarrassment, coupled with his stated dedication to changing the show's discourse, made it believe suspension was the appropriate response.
"Our future relationship with Imus is contingent on his ability to live up to his word," the network said.
CBS Radio released a statement promising to monitor the show's content in the future. "We are disappointed by Imus' actions last week, which we find completely inappropriate," the statement read. "We fully agree that a sincere apology was called for and will continue to monitor the program's content going forward."
Imus, who has made a career of cranky insults in the morning, was fighting for his job following the joke that by his own admission went "way too far." He continued to apologize Monday, both on his show and on a syndicated radio program hosted by the Rev. Al Sharpton, who is among several black leaders demanding his ouster.
Imus could be in real danger if the outcry causes advertisers to shy away from him, said Tom Taylor, editor of the trade publication Inside Radio. The National Organization for Women is also seeking Imus' ouster.
"Everyone is on tenterhooks waiting to see whether it grows and whether the protest gets picked up more broadly," Taylor said.
Imus may be in hot water with his network and his listeners, but he's got nothing to fear from the Federal Communications Commission, reports CBS News correspondent Nancy Cordes.
The government agency that regulates the radio and television airwaves can levy big fines for sexual content it terms "indecent." But the FCC has no jurisdiction over comments that are considered racist or in plain bad taste. Racist remarks are policed by no one but the broadcasters themselves.
Imus isn't the most popular radio talk-show host — the trade publication Talkers ranks him the 14th most influential — but his audience is heavy on the political and media elite that advertisers pay a premium to reach. Authors, journalists and politicians are frequent guests, and targets for insults.
He has urged critics to recognize that his show is a comedy that spreads insults broadly. Imus or his cast have called Colin Powell a "sniffling weasel," New Mexico Gov. Bill Richardson a "fat sissy" and referred to Sen. Ben Nighthorse Campbell of Colorado, an American Indian, as "the guy from `F Troop."' He and his colleagues also called the New York Knicks a group of "chest-thumping pimps."
On Sharpton's program Monday, Imus said that "our agenda is to be funny and sometimes we go too far. And this time we went way too far."
Imus made his remark the day after the Rutgers team, which includes eight black women, lost the NCAA women's championship game to Tennessee. He was speaking with producer Bernard McGuirk and said "that's some rough girls from Rutgers. Man, they got tattoos ..."
"Some hardcore hos," McGuirk said.
"That's some nappy-headed hos there, I'm going to tell you that," Imus said.
The Rutgers comment has struck a chord, in part, because it was aimed at a group of young women at the pinnacle of athletic success. It also came in a different public atmosphere following the Michael Richards and Mel Gibson incidents, said Eric Deggans, columnist for the St. Petersburg Times and chairman of the media monitoring committee of the National Association of Black Journalists. The NABJ's governing board, which doesn't include Deggans, wants Imus canned.
On his show Monday, Imus called himself "a good person" who made a bad mistake.
"Here's what I've learned: that you can't make fun of everybody, because some people don't deserve it," he said. "And because the climate on this program has been what it's been for 30 years doesn't mean that it has to be that way for the next five years or whatever because that has to change, and I understand that."
New Jersey Gov. Jon S. Corzine spoke to Rutgers players Monday and said later that he strongly condemned Imus' words.
"There is absolutely no excuse for his conduct, and he is right to apologize," Corzine said. "Only the Rutgers women's basketball team, however, can decide to accept his apology. If Mr. Imus really wants to go and learn from this, he should watch how these young ladies carry themselves. He might just learn from their example."
Rutgers players said they planned to make a public statement on Tuesday.
Arizona Republican Sen. John McCain, whose presidential candidacy has been backed by Imus on the air, said he would still appear on Imus' program.
"He has apologized," McCain said. "He said that he is deeply sorry. I'm a great believer in redemption. Whether he needs to do more in order to satisfy the concerns of people like the members of that team, that's something that's between him and them. But I have made many mistakes in my life ... and I have apologized, and most people have accepted that apology."
Imus' radio show originates from WFAN in New York City and is syndicated nationally by Westwood One, both of which are managed by CBS. The show reached an estimated 361,000 viewers on MSNBC in the first three months of the year, up 39 percent from last year. That's the best competitive position it has ever achieved against CNN (372,000 viewers).
Imus' fate could ultimately rest with two of the nation's most prominent media executives: CBS Corp. chief Leslie Moonves and Jeff Zucker, head of NBC Universal.
"He will survive it if he stops apologizing so much," said Michael Harrison, publisher of Talkers. Imus clearly seems under corporate pressure to make amends, but he's nearly reached the point where he is alienating the fans who appreciate his grumpy outrageousness.
Even if he were to be fired, he's likely to land elsewhere in radio, Harrison said.
The Rev. Jesse Jackson and about 50 people marched Monday outside Chicago's NBC tower to protest Imus' comments. He said MSNBC should abandon Imus and MSNBC should hire more black pundits.
Julian Bond, chairman of the NAACP board of directors, said it is "past time his employers took him off the air."
"As long as an audience is attracted to his bigotry and politicians and pundits tolerate his racism and chauvinism to promote themselves, Don Imus will continue to be a serial apologist for prejudice," Bond said.
Imus was mostly contrite in his appearance with Sharpton, although the activist did not change his opinion that Imus should lose his job. At one point Imus seemed incredulous at Sharpton's suggestion that he might walk away from the incident unscathed.
"Unscathed?" Imus said. "How do you think I'm unscathed by this? Don't you think I'm humiliated?"