May-dong Sung entered business first at Hankow and later at Shanghai. He was a manager of the May War Lee Watch and Clock Co., at Shanghai, a director of the Ningpo-Shaoshing Steam Navigation Co. the Shanghai Ningpo Guild and the Ningpo Hospital. Mr. Sung was also a member of the board of directors of the Shanghai Chinese General Chamber of Commerce for several years, general-manager of the Hope Brothers & Co., Shanghai, a philanthropist and founder of schools.
Then he became an anti-opium worker and in 1917, in conjunction with a few friends, purchased one of the largest opium smoking houses in Shanghai and converted it into a commercial museum, destroying the opium smoking paraphernalia by fire before a public audience.
May-dong Sung was awarded two memorial tablets by the President of China.