The Russian leader said the cables released by the whistle-blowing site WikiLeaks show a "full measure of cynicism" that is prevalent in foreign policy, RIA Novosti reported.
Among other things, the diplomatic cables allege Russian Prime Minister Vladimir Putin likely knew of the plot to kill a former KGB agent and described Russia as a "virtual mafia state."
"We are not paranoid and we do not link Russian-American relations with any leaks, although the leaks are revealing," Medvedev said. "They show a full measure of cynicism of those evaluations and judgments that often prevail in the foreign policy of various states; in this case, I am referring to the United States."
The president said U.S. officials would "get a lot of pleasure" from Russian diplomatic cable traffic.
Putin earlier this week told CNN "political purposes" may be behind the leaks but they posed "no catastrophe."
The communiques are among the more than 250,000 diplomatic cables WikiLeaks offered for publication to several newspapers. The documents included communications about U.S. policy in Iran, Pakistan, Korea and other places. WikiLeaks earlier this year leaked information about the U.S. wars in Iraq and Afghanistan.