HONG KONG—Asian buyers have thus far dominated the week’s Sotheby's art auctions here, breaking at least one record and causing some bidders to claim that it is difficult to compete with them.

Monday’s record-breaker was a 1984 scroll by Li Keran, which sold for HK$7.3 million ($940,000), high above a top estimate of HK$4.5 million and the most ever paid at a Hong Kong auction. Additionally, Lotus et Poissons Rouges, a painting by Chinese master Sanyu, sold to a mainland Chinese buyer for HK$36.5 million ($4.7 million) at another auction. The high estimate was HK$25 million.

Bidders noted that the healthy market, with many pieces selling above estimates, was due to the large number of Asian, and specifically Chinese, buyers in attendance. In fact, mainland Chinese buyers accounted for the top lots in each category of the second Sotheby’s sale. China’s economy has improved over the past year, with wealth increasing as the Shanghai stock index makes gains. Said collector Eddie Leung, “It’s very clear the Chinese are holding up Asia’s art market. It’s great if you’re a seller, but awful if you’re bidding against them.”

Read more at Bloomberg News.