Actress Juliana "JuJu" Chan Yuk-wan has started a campaign calling for the introduction of women-only carriages on MTR trains.
Chan, who also wants to see designated women-only waiting areas on platforms, delivered a petition to MTR headquarters yesterday.
The move followed an incident last Friday in which Chan was molested, while waiting on the platform at Admiralty station at 6pm during the rush hour.
"When I turned around to try to catch the person, I couldn't tell who it could have been," she said.
"I felt very angry and helpless. But then I thought I could help raise awareness about a prevalent problem about which many women keep silent."
Chan filed a police report on Friday night and is waiting for a review of security video footage to try to identify her assailant.
Many countries in the region have adopted protective measures for female travellers. Japan, India, Taiwan, Indonesia and Seoul have all installed women-only subway compartments.
However, an MTR spokeswoman said the corporation had no plans to install female-only carriages for logistical reasons.
"Because most MTR trains have an open design, creating female-only carriages would affect customer flow between carriages and emergency exit arrangements," she said.
She added it would be difficult for staff to prevent male passengers from going through women-only areas.
Angie Ng, organiser of SlutWalk Hong Kong, an annual march against sexual assault, said that gender segregation should be only a temporary solution.
"In the long term, social attitudes need to be changed so that sexual harassment is taken seriously by the public and seen as the perpetrator's fault, not the victim's," Ng said.
"The MTR, the police and the government need to work together to take concrete action in punishing offenders."
Chan agreed, saying she had seen bystanders stay silent when they witnessed a woman being assaulted. "This isn't just the victim's problem and we need to look out for each other," she said.
"In an equal society, everyone should feel safe."
Police figures show there were 151 reports of indecent assault in 2010, 167 last year and 131 by the end of last month.