In a statement issued on KCNA, Pyongyang said Biden, who could be leading the Democratic nominee to challenge President Donald Trump in 2020, had made "ludicrous statements" about Kim Jong Un that are also blasphemous.
During a rally in Philadelphia on Saturday, Biden said Trump was embracing "dictators and tyrants" like Russia's Vladimir Putin and Kim.
The mention of Kim's name could be triggering a strong response from the North Korean regime, where leadership idolization is state policy.
In the commentary titled "The disgraceful behavior of a Philistine without even the basic qualities of a human being," North Korea said Biden had a habit of "speaking to women in a vulgar language," and that even in the Democratic Party "fingers are being pointed" at Biden for his behavior.
North Korea also said in the United States Biden is being evaluated as a "low IQ dummy" and that Americans are "not holding too high expectations" about the presidential candidate.
Pyongyang mocked Biden in the statement: It is worth "having a good laugh" over Biden's popularity, North Korea said.
"He cannot even distinguish what is coming out of his mouth as he grins in a dumbfounded manner," North Korea said. Pyongyang also noted that Biden previously lost the presidential nomination twice.
North Korea has sharpened its rhetoric since the collapse of the Hanoi summit. Pyongyang has called for sanctions relief but Washington recently seized a North Korea cargo ship.
North Korea's top envoy to the United Nations Kim Song accused the Trump administration of violating international law on Tuesday. The U.S. State Department said in response Trump "believes" Kim will fulfill his commitments to denuclearize, Radio Free Asia reported.