Previously a flight stewardess with Singapore Airlines, Sharon's career in the entertainment industry began when she was talent-spotted from a Toy Factory Productions English remake of a Hong Kong stage musical I Have A Date With Spring. During the late 1990s she was best known for co-hosting City Beat with Kym Ng and Bryan Wong. She played numerous roles ranging from a cabaret girl in the stage musical, Beauty World to an enthusiastic radio presenter in the sitcom Right Frequency, each receiving rave reviews.

Competent and effectively bilingual, Au proved to be one of the more established hosts in Mediacorp alongside Quan Yi Fong and Guo Liang. This is further endorsed with her victory when she clinched the Star Awards for Best Variety Show Host for four consecutive years from 2000 to 2003.

Sharon made a decision and left the entertainment industry during peak in her career and went to Japan to further her studies in 2005 in the School of International Liberal Studies, Waseda University in Tokyo on a MediaCorp scholarship. As part of her studies, she went to Jean Moulin University Lyon 3 in France for a year to study, as part of Waseda University's One-Year international Exchange Program. Sharon is blessed with the gift of picking up languages quickly and she is proficient in English, Chinese, Japanese, French and basic Spanish.

Sharon was invited back on a few occasions to be host for some key events, including being the host in Beijing for Singapore Prime Minister's first state visit there and Star Awards 2007. In April 2011, she went back to MediaCorp to serve her 6 years bond. She played host for President Star Charity show in 2012 . She made a significant mark in her forties; being one of the 3 key hosts in SEA Games in Singapore's home ground. In the same year; she played the female lead, Madam Kwa Geok Choo, in The LKY Musical, alongside with actor Adrian Pang, for 37 shows in the Marina Sands Theatre.

In 2012, she started and led (a property of MediaCorp Pte Ltd), focusing fashion, beauty and lifestyle. In 2016, she co-founded the Style by Style Vibes cafe when the new Mediacorp campus opened. In 2017, she was appointed as the Publisher for ELLE Singapore as part of Mediacorp's move from print to digital for its print medium.

On 4 January 2018, Sharon left Mediacorp and is currently an investment director with the private equity firm in Paris, France.