Ombudsman Winnie Chiu on Thursday urged the government to tighten medical requirements for older drivers, given that there are now so many on the territory's roads.
From the age of 70, when motorists renew their driving licences every three years they have to submit a medical certificate to prove they are fit to drive.
But exactly what medical checks they need to go through to determine their suitability for driving isn't specified.
An investigation by the Ombudsman has found that Hong Kong's requirements are lax compared to some other places, including the mainland, Singapore, Australia and Canada.
The watchdog noted that there were more than 73,000 drivers aged 70 or above last year – almost double the number in 2016 – and it called on the Transport Department to specify what doctors should examine to asses how fit elderly people are to drive.
"In view of the ageing population, the proportion of elderly drivers is going to rise. People's vision, physical fitness, reaction and cognitive ability may weaken as they age, affecting their ability to drive," the Ombudsman said in its report.
The watchdog also recommended more stringent requirements for drivers of commercial vehicles reaching a specified age.
Currently, only bus and tram drivers are required to undergo regular medical checks.
"Given that commercial vehicles are bulky and they carry a large amount of goods or passengers, traffic accidents and collisions involving commercial vehicles can have dire consequences," the report said.