Here is my list. I know that some will disagree – but I am stopping at 6 to let you add 4 more. Perhaps it is too classic, but here they are, in order of subjective importance:
1. THE PAINTED VEIL by Somerset Maugham A novel published in 1925. The title comes from Percy Bysshe Shelley’s sonnet which begins “Lift not the painted veil which those who live / Call Life”. Originally the main characters were called Lane not Fane but a couple of that name in Hong Kong successfully sued the magazine publishers of the initial serialised version for libel and won £250. To avoid similar problems after A. G. M. Fletcher, the then Assistant Colonial Secretary in Hong Kong, also threatened legal action, the name of the colony was changed to Tching-Yen. Later editions reverted to Hong Kong but the name Fane was kept for all editions.This novel was first serialised form in five issues of the Cosmopolitan (November 1924 – March 1925). William Somerset Maugham (25 January 1874 – 16 December 1965) was a British playwright, novelist and short story writer.
2. 
THE HONOURABLE SCHOOLBOY by John le Carré. It is a spy novel published in 1977 by British author and former spy David John Moore Cornwell (born 19 October 1931), pen name John le Carré.
3. LOVE IS A MANY-SPLENDOURED THING by Han Suyin. Set in 1949–50 Hong Kong, it tells the story of a married, but separated, American reporter Mark Elliot who falls in love with a Eurasian doctor Han Suyin originally from China only to encounter prejudice from her family and from Hong Kong society. Hán Sùyīn; 12 September 1916 or 1917 – 2 November 2012) was the pen name of Elizabeth Comber, born Rosalie Matilda Kuanghu Chou (Chinese: 周光瑚; pinyin: Zhōu Guānghú). She was a China-born Eurasian, a physician, and author of books in English and French on modern China, novels set in East and Southeast Asia, and autobiographical memoirs which covered the span of modern China. She lived in Lausanne until her death.
4. HONG KONG HOLIDAY by Emily Hahn. It was published in 1946. Hahn (Chinese: 項美麗, January 14, 1905 – February 18, 1997) was an American journalist and author. Called “a forgotten American literary treasure” by The New Yorker Magazine, she was the author of 52 books and hundred of articles and stories. Her writings in the 20th century played a significant role in disclosing Asia to the West. Even this wonderful book set in Hong Kong during the Japanese the first part of the Japanese occupation has been forgotten and never reprinted since the first edition. Hahn was a bizarre caracter, an extremely beautiful and intelligent woman who kept two monkeys in her apartment in Conduit Road. Colonel Boxer, the british historian, abandoned his wife and daughter to marry her.
5. THE WORLD OF SUZIE WONG By Richard Mason. This is a 1957 novel. The main characters are Robert Lomax, a young British artist living in Hong Kong, and Suzie Wong, the title character, a Chinese woman who works as a prostitute. Richard Mason (16 May 1919 – 13 October 1997) was a British novelist.
5. HONG KONG by Jan Morris, was first published in 1988. She was born James Humphrey Morris, on 2 October 1926 and she is known particularly for the Pax Britannica trilogy (1968–78), a history of the British Empire, and for portraits of cities, notably Oxford, Venice, Trieste, Hong Kong, and New York City. She is a trans woman and was published under her birth name until 1972, when she transitioned from living as male to living as female.