Its staggering haul included a record $58.4 million for a Jackson Pollock drip painting, which shattered all previous records for the highest price for any work at an art auction.
"We are thrilled to announce an unprecedented overall total of $638.6 million for this week's Post-War and Contemporary Art sale series," said Brett Gorvy, an official at Christie's.
Sotheby's, meanwhile, had stellar overall sales of $377.4 million, including the sale of the work "Domplatz, Mailand" (Cathedral Square, Milan) by German painter Gerhard Richter for $37.1 million -- a record for a living artist.
The other sensation for Sotheby's was a work by US painter Barnet Newman, one of the leading figures of abstract expressionism, whose "Onement VI" fetched $43.84 million -- the most ever for one of his paintings.
Gorvy said the record prices "reflect a new era in the art market, wherein seasoned collectors and new bidders compete at the highest level within a global market."
Pollock's "Number 19, 1948," executed in his iconic drip-paint style with a shimmering mixture of silver, black, white, red and green, had been expected to sell for between $25 million and $35 million.
But it shot up to set a new auction high for the artist. The previous top auction price for a Pollock had been $40.4 million last year, although his paintings are said to have sold for far more in unconfirmed private deals.
Meanwhile one-time graffiti artist Jean-Michel Basquiat also set a record, sailing past Christie's $25 million to $35 million pre-sale estimate to $48.8 million.
It was the highest auction price ever for the young artist, who died in 1988 of a heroin overdose in New York, aged just 27.