Tadamasa Hayashi

 was a Japanese art dealer who introduced traditional Japanese art such as ukiyo-e to Europe.
Tadamasa was born to the Nagasaki family of physicians. When he was still a child, he was adopted into the Hayashi family, an upper-class samurai family of Toyama-han. He then attended the University of Tokyo. In 1878, he went to Paris as a translator to seek a new life abroad. In Paris, he began a career as Japanese art dealer.
Hayashi provided the text for the May 1886 edition of "Paris Illustré". Vincent van Gogh traced the figure on the title page for his painting "The Courtesan". In 1900 he was a general commissioner of the Japanese art section at the World 's Fair in Paris.
He also worked with Dr. George Frederick Kunz and Heber R. Bishop in writing and producing the catalog to the famous jade collection given to the Metropolitan Museum of Art in 1902.