Dr Hnin Saing obtained her medical degree from The University of Hong Kong in 1998 and completed her internship training across major public hospitals in Hong Kong, rotating through paediatrics, internal medicine, and surgery.

She subsequently served as a Medical Officer in Anaesthesia and Intensive Care at Queen Mary Hospital before joining the School of Public Health at The University of Hong Kong in 2003. During her time with the University, her responsibilities encompassed academic research, curriculum development, and medical student education, alongside pursuing further postgraduate studies in public health.

Dr Saing first joined Marina Medical in 2016, practising with the clinic through 2022. She rejoined the medical practice in 2026, continuing to provide patient care to the community.