Under this mechanism, airlines were temporarily banned from flying if they were found to be carrying five or more passengers infected with the Covid-19 virus.
This caused unnecessary trouble and inconvenience for inbound passengers, the government said.
The latest move is expected to help students who are studying abroad and wish to return home.
It follows a preliminary review of data and scientific analysis, which found that improved and regular nucleic acid testing on passengers is more effective in preventing the spread of the virus.
In a statement, a government spokesman said: “The decision to implement the new measures was made upon careful review of relevant data, and the fact that it is currently the peak period for students studying aboard to return to Hong Kong.
“The relevant measures can help reduce the impact on inbound persons, and will particularly enable young people staying in overseas places to return to Hong Kong smoothly to reunite with their families during the summer holiday.
“The measures will also prevent the transmission of imported cases into the community in a more precise and effective manner, in order to maximise the anti-epidemic effectiveness with the lowest social costs.”
However, the government has mandated that inbound passengers must take another Covid-19 test on the third day of their quarantine.
Meanwhile, Hong Kong International Airport (HKIA) has begun flight operations on its new third runway.
The development is part of the $18bn three-runway system (3RS) project, which also involves the expansion of Terminal 2 (T2), development of a new T2 Concourse, and addition of an automatic people mover and baggage handling system.
Work on the project is expected to be completed by 2024.