Sham was one of 28 top competitors invited to play in person at the competition in Fort Worth, although 340 pianists from 45 countries and regions took part.
In addition to winning US$100,000 in prize money, the 29-year-old will also get artistic and publicity support from the organisers for three years, along with career management.
His mother, who teaches the piano, told RTHK that she was glad her son came out on top, saying Sham had enjoyed the process despite the difficulties.
She also said she had raised Sham just like any other mother, saying he had forged his own path since he went abroad to study.
Born in Hong Kong, Sham started playing the piano at the age of three.
He studied at Harrow School in London and graduated from Harvard University, before completing a master’s degree in music at the New England Conservatory.
Sham has won numerous international competitions. He has also performed for former President Hu Jintao, King Charles of the United Kingdom, and Belgium’s Queen Mathilde.