"Rumsfeld whose political faith is to establish the US-style world order by strength is known to be a typical stupid man for professing neo-conservatism censured and mocked at worldwide," North Korea's official Korean Central News Agency (KCNA) said late Saturday.
The angry remarks came after Rumsfeld reportedly told US and South Korean business leaders last week that he had a night-time satellite picture of the divided peninsula showing North Korea almost entirely in darkness.
KCNA said, "He told nonsense that it is necessary to make sure that the rays of freedom reach the oppressed North Koreans, asserting that a satellite photo shows the rays of freedom on one part of the Korean peninsula and the darkness of dictatorship on the other part of it and communism is shaking on its own."
It said the remarks proved he was "just an old man (and) politically illiterate" who could not face the reality that "all countries are promoting peaceful co-existence, reconciliation and cooperation irrespective of ideologies and beliefs."
The news agency said Rumsfeld was "obsessed with wantonly harassing peace and security in different parts of the world and igniting wars."
"He is, therefore, not a guy who the DPRK (North Korea) can deal with," it said.
Pyongyang blamed US hostility for the collapse of six-way talks on the nuclear crisis held in Beijing last month.
Washington has insisted that North Korea scrap its nuclear weapons drive before it would consider offering the Stalinist state concessions, including economic and security benefits.
North Korea says it wants the security of its regime guaranteed by the United States through a legally binding non-aggression pact before it will address the nuclear issue.