The woman in her 80s who died from coronavirus over the weekend in Canberra contracted COVID-19 while on board the Ruby Princess cruise ship.
Health Minister Rachel Stephen-Smith disclosed the information on Tuesday afternoon at the request of the woman's family.
At least six people connected to the ship have now died from coronavirus, while a total of 211 passengers have been infected.
The ACT recorded three new case of coronavirus over the past 24 hours, all of which were linked to overseas travel. The new cases ranged in age from 27 to 57.
Health authorities say one person who had previously been counted as among the confirmed cases of coronavirus had had their case investigated and had now been determined to not have COVID-19. The total number of cases in the ACT stands at 80.
ACT chief health officer Dr Kerryn Coleman said the patient who had been cleared of coronavirus did not test positive or negative after initial tests, but was classified as a coronavirus patient as a precaution.
"We received an indeterminate result and we then acted with contact tracing moving forward," Dr Coleman said.
"But we later found it wasn't a positive result."
While the chief health officer said there had been fewer cases of coronavirus recorded in recent days as international travellers return home, she warned Canberrans not to be complacent about COVID-19.
"We are anticipating some level of community transmission in the ACT, and as a result, we are expecting more cases," Dr Coleman said.
"Because we're a jurisdiction that has implemented contact tracing extremely well and because there's not as much international travel, we've seen an improvement [in the number of cases].
"But we need to remind to community that we will end up as other jurisdiction."
At Tuesday's media conference, Ms Stephen-Smith clarified previous comments in which she claimed authorities were making daily check-ups on everyone who was required to be in mandatory quarantine.
She said authorities were contacting all of the ACT's COVID-19 cases and their close contacts, as well as anyone who health protection knew had recently returned from overseas.
But she said authorities weren't able to keep track of other people known to have recently returned from overseas, as Border Force had been slow to provide them with their contact details.
While stressing that she didn't want to be critical of the agency, Ms Stephen-Smith said the information sharing had not been as "quick as we might have wanted it to be".
She pointed to sheer scale of data being processed as the reason for the delays.
We have removed our paywall from our stories about the coronavirus. This is a rapidly changing situation and we want to make sure our readers are as informed as possible. If you're looking to stay up to date on COVID-19, you can also sign up for our twice-daily digest here. If you would like to support our journalists you can subscribe here.