The milestone was achieved at the start of Wednesday trading - just after the opening bell sounded.
It had been on the cards for some time, given the rally in US stocks since the election of Donald Trump as US President - with investors cheering his stated plans for a major infrastructure investment programme and other business-friendly policies.
The rally in stock values faltered in the weeks before the tycoon's inauguration - coming within one point of 20,000 on 6 January.
Market participants credited Trump's announcements on Tuesday, to advance two major pipeline projects blocked by former president Barack Obama, for the surge in the Dow's performance on Wednesday.
It was 0.7% higher within the first hour of trading at 20,051, with analysts saying the continued climb in value was down to investment through "FOMO" or the "fear of missing out."
The President himself, in typical fashion, took to Twitter to deliver his reaction saying: "Great #Dow20k"
European stock markets were firmly in positive territory before the Dow's achievement was reached but gains were extended in Germany, France, Italy and Spain. The DAX in Frankfurt was 1.8% higher in late trading.
The FTSE 100 struggled to keep up, with gains of just 0.3%, as a weaker dollar versus the pound made UK stocks slightly less attractive.
London's top flight index hit record levels itself this month as many of its dollar-earning constituents have benefited from sterling's collapse in value since the Brexit vote.
The pound was trading at $1.2601 by mid-afternoon - up 0.6% on the day.
Neil Wilson, senior markets analyst at ETX Capital, said the push above 20,000 for the Dow "really confirms that the 'great rotation' from bonds to stocks is definitely upon us.
"Fears about protectionism are running second to optimism about inflation and growth - for now at least.
"Donald Trump's election victory, far from roiling markets, has been greeted with universal optimism about what it means for global growth.
"Something like $3tn has been pulled from bonds and $3tn pumped into equities.
"President Trump is bound to take credit for the rally, and he may well be justified to some degree."