Papadopoulos served as a foreign policy adviser to President Trump's 2016 campaign, and was the first to plead guilty in the Mueller probe.
Appearing in federal court, the former businessman was sentenced to 14 days in prison for lying to federal investigators employed by special counsel Robert Mueller.
Papadopoulos, 31, pleaded guilty in October 2017 to a charge of making false statements to investigators about his contacts with Russian Federation.
President Donald Trump and his allies have repeatedly downplayed Papadopoulos' role on the campaign.
According to Politico's Kyle Cheney, the Papadapoulos' lawyer blamed Trump saying, "The president of the United States hindered this investigation more than George Papadopoulos ever could", citing the president's attacks on the investigation as a "witch hunt" and "fake news".
Lawyers for Mr. Papadopoulos dispute some of the government's characterizations, and they asked the judge to sentence him to probation.
Papadopoulos, who was initially interrogated on January 27, 2017 by Federal Bureau of Investigation agents regarding his work for the Trump campaign, was arrested at Washington-Dulles International Airport on July 27, 2017 and arraigned the following day.
In his pre-sentencing statement, Papadopoulos admitted lying to FBI investigators in January 2017 but said it had been out of a desire to protect his career and a naive loyalty to the Trump administration.
The Russian outreach to Papadopoulos was part of a sweeping active measures campaign aimed at the United States that also included overtures toward other political operatives, cyberattacks, agitation on social media and more. That's the only thing I know about him.
He later attempted to use his links to the professor and Russian nationals to attempt to set up a meeting between Trump and Russian President Vladimir Putin. Instead, prosecutor Andrew Goldstein said he made "at best grudging efforts to cooperate, and we don't think they were substantial or significant in any regard".
"Papadopoulos misled investigators to save his professional aspirations and preserve a perhaps misguided loyalty to his master", the lawyers wrote.
Papadopoulos obtained a plea deal at the time, which was subsequently unsealed last October.
Papadopoulos disagreed in his own court filing, arguing he "cooperated fully" and provided "critical information".