Some Chinese netizens have criticized the casting, saying Lau, 53, and Jiang, 36, were "old" to play the characters as depicted in the book.
"I don't know why they care about age," Lau says, adding that she believes a good actress can "become" any role no matter how far the character is from her own life.
The series, which also casts actor Guo Xiaodong and Taiwan actor Joe Cheng, is scheduled to run on Beijing Satellite TV and streaming site iQiyi around the end of May.
