"I ask you to be as merciful as a human being can be," said Jones, who cried on her husband's shoulder after she was sentenced.
The disgraced former Olympic champion was ordered to surrender March 11 to begin her term.
U.S. District Judge Kenneth Karas said he gave her the maximum under the plea deal to send a message to athletes who have abused drugs and overlooked the values of "hard work, dedication, teamwork and sportsmanship."
"Athletes in society have an elevated status, they entertain, they inspire, and perhaps, most important, they serve as role models," Karas said.
Later Friday, Karas was to sentence Jones' former coach, Olympic champion Steve Riddick, who was convicted in the check-fraud scam.
The 31-year-old Jones also was given two years' probation and supervised release, during which she will be required to perform 800 hours of community service.
"As everyone can imagine, I'm very disappointed today," Jones told reporters outside court. "But as I stood in front of all of you for years in victory, I stand in front of you today. I stand for what is right."
"I respect the judge's order, and I truly hope that people will learn from my mistakes," added Jones.
The judge said Jones' community service requirement would take advantage of her "eloquence, strength and her ability to work with kids."
It was her children that worried Jones as she pleaded for a lighter sentence, talking at length about her two boys, including the infant son she's still nursing.
"My passion in life has always been my family," Jones said. "I know the day is quickly approaching when my boys ask me about these current events. I intend to be honest and forthright ... and guide them into not making the same mistakes."
The sentence completes a stunning fall for the woman who was once the most celebrated female athlete in the world. She won three gold and two bronze medals at the 2000 Sydney Olympics.
After long denying she ever had used performance-enhancing drugs, Jones admitted last October she lied to federal investigators in November 2003, acknowledging she took the designer steroid "the clear" from September 2000 to July 2001. "The clear" has been linked to BALCO, the lab at the center of the steroids scandal in professional sports.
"I think athletes have been under the misconception for a long time that they're untouchable and here, you lie to a prosecutor and you go down for perjury," Sports Illustrated writer Luis Fernando Llosa told CBS News correspondent Michelle Miller.
Jones also admitted lying about her knowledge of the involvement of Tim Montgomery, the father of her older son Monty, in a scheme to cash millions of dollars worth of stolen or forged checks. Montgomery and several others have been convicted in that scam.
"The revelation that one of the sport's biggest stars took performance-enhancing drugs and repeatedly lied about it, in addition to being a party to fraud, has no silver lining," USA Track & Field president Bill Roe and CEO Craig Masback said in a statement. "But, it is a vivid morality play that graphically illustrates the wages of cheating in any facet of life, on or off the track."
After her guilty pleas last October, Jones made an apologetic and teary-eyed statement outside court, saying, "It's with a great amount of shame that I stand before you and tell you that I have betrayed your trust."
"I have been dishonest, and you have the right to be angry with me," she added. "I have let (my family) down. I have let my country down, and I have let myself down. ... I want to ask for your forgiveness for my actions, and I hope you can find it in your heart to forgive me."
Bay Area Laboratory Co-Operative founder Victor Conte, who served four months in prison after pleading guilty to operating a steroids distribution ring, said Friday he felt sad for Jones and her family.
"Marion did make some very poor choices, and she does deserve serious consequences. I certainly don't condone her repeated lies," Conte said in a statement. "There is no doubt in my mind that she has learned gigantic lessons. Hopefully, she will be able to serve as an example and help others to make good decisions."
Jones returned her Olympic medals - golds in the 100 meters, 200 meters and 1,600-meter relay and bronzes in the long jump and 400-meter relay - even before the International Olympic Committee ordered her to do so and wiped her results from the books.
She was among the many athletes who testified in 2003 before a grand jury investigating BALCO. And on the day she pleaded guilty, prosecutors said a 2003 search warrant at BALCO uncovered ledgers, purchases, doping calendars, and various blood-test results connected to Jones and former coach Trevor Graham.
She took EPO, human growth hormone and THG using drops and injections, according to the court documents that show use in 2000 and 2001.