Emergency intercoms were installed at Queen St and King St taxi ranks last month.
The federally-funded technology was launched on July 2.
When pushed, the emergency intercom buttons connect to the City of Melbourne’s CCTV control room and capture images of the person who pressed the button.
The two new emergency intercoms bring the total to four within the CBD, with existing intercoms operating in Flinders St and Bourke St.
There are now 68 CCTV cameras operating within the wider City of Melbourne, including a mobile CCTV patrol vehicle capable of capturing 360-degree footage.