Government House (with new wing on the left)

Image from My Colonial Service in British Guiana, St. Lucia, Trinidad, Fiji, Australia, Newfoundland, and Hong Kong with Interludes by William Des Vœux (published in 1903).

The new wing opened in September 1891. 

Des Vœux was governor of Hong Kong from 1887-1891. The photo could be from the end of his term, likely taken a few years later but before 1903.