Professor Siu graduated from The Chinese University of Hong Kong and the University of Sydney. After completing her specialist training in otolaryngology, she pursued further studies in the subspecialty of pediatric otolaryngology. Adhering to her motto "Every child, unlimited potential", she is committed to helping all children realize their potential regardless of their backgrounds. Professor Siu is passionate about mentoring female students and young professionals, striving for gender equality in the medical field.

She currently holds the positions of Acting Assistant Dean (Clinical Education), Program Director for the third and fifth years of the Clinical Medicine program, and Vice President of the Second Affiliated Hospital of The Chinese University of Hong Kong, Shenzhen. She is also a Member of the Royal College of Surgeons of Edinburgh, Fellow of the Royal College of Surgeons of Edinburgh in Otolaryngology, Fellow of the Hong Kong Academy of Medicine (Otolaryngology), and Fellow of the Hong Kong College of Otolaryngologists.