With one of China's top auction houses about to open an office in New York, it's tempting to say the Chinese are coming. But they've been here for a while.

China Guardian Auctions Co. will officially open a satellite this month on Park Avenue near 59th Street—a big player joining a local auction-house landscape dominated by Sotheby's and Christie's.

But in an effort to keep pace with an expanding market back home, its representatives have been in the city for the past five years, meeting collectors and sourcing traditional Chinese art (porcelain, jade carvings, calligraphy, ink paintings) and cultural relics.

"The United States has a long history of collecting Chinese traditional arts, privately and in the museum system," said Asia Society's museum director, Melissa Chiu. "I think China Guardian setting up an office in New York city is in some way a recognition of that."

China Guardian is sourcing in New York, but it won't be selling here. All of its auctions are held in Beijing, where there is much higher demand for traditional Chinese art and a stronger market, said Kou Qin, a director and vice president. About 40% of the pieces in China Guardian auction lots are sourced from the U.S., Europe and Australia.

"Ninety percent of our buyers are mainland Chinese, but it is the same situation for the whole Chinese art market," Mr. Kou said. "The Chinese art market is booming very rapidly and the prices are going up, so of course Chinese art works can be sold at a higher price in China."

China has a long tradition of art and artifacts, but its art market is young. Founded in 1993, China Guardian is its oldest art auction house, and among its most profitable. In an effort to fill the rising market demand, China Guardian will now have one staffer in New York full time and two others based in New York but traveling across the U.S. to meet with collectors in possession of valuable Chinese art.

"The story of the last decade is the increasing dominance of Chinese buyers at Chinese art auctions," said New York dealer James Lally. "When one attends auctions in London or New York or Hong Kong, one tends to see the same faces, and see the same content and general results. More than ever now we have Chinese buyers...allowed by the government to attend sales elsewhere. There's really one international market for Chinese art."

Talk spread this summer of both China Guardian and competitor Beijing Poly International Auction Co. opening offices in New York by year's end. A Beijing Poly representative confirmed plans to have a sourcing liaison in New York, but said a specific site or date had not yet been set.

Meanwhile, China Guardian is conspicuously magnifying its presence in the local market. New York, with its storied history of collectors, galleries and museums, offers proximity to pieces that have long been in the U.S. but may fetch higher prices in China.

"There is a sense of provenance that is very much sought-after," said Henry Howard-Sneyd, the vice chairman of Asian art at Sotheby's. "Collectors like to know that pieces were in museum shows over a long period of time—the sense of history and security and authenticity. By selling a piece from a New York collection in New York, you're very much encompassing that provenance."

(Earlier this year, Sotheby's sold several hundred works of art from the collection of the late Chinese-born New York dealer J.T. Tai. A vase thought to be from the much-coveted era of the Qianlong emperor topped $18 million.)

It may seem odd that Chinese auction houses look to foreign tastes in valuating Chinese art, but some believe the market is being driven by far more practical forces.

"The Chinese have various reasons for wanting to buy things," Mr. Lally said. "They will speak in terms of repatriating treasures to the homeland, but when it comes right down to it, it has to do with price and it has to do with quality."

Mr. Kou conceded that there are "some cultural elements" involved in the appeal of traditional Chinese art to Chinese buyers, saying that Chinese are especially sensitive about relics from the Qing dynasty's Winter Palace, which was looted and burned by British and French forces in the 1860.

But when it comes to buying art, he said, "I don't think that is the mainstream. The mainstream is that now Chinese people are becoming wealthier and have the capability to buy art."

With the New York expansion, Mr. Kou emphasized participating in art expositions and consigning significant collections.

In 2007, the Museum of Fine Arts in Boston consigned to China Guardian 39 pieces of Qing dynasty porcelain and 287 rare books that it had deaccessed after a "normal housekeeping" survey. The MFA went with China Guardian after submitting proposals to multiple companies "because they are clearly the leader in the field," said MFA Deputy Director Katie Getchell.

While he would not divulge names, Mr. Kou said China Guardian is in talks with New York collectors about similar consignments, though it has no current plans to hold auctions in New York.

It does, however, intend to start researching the market for non-Chinese art. That endeavor, Mr. Kou said, depends on the market.