Portuguese Economy Minister Pedro Siza Vieira tested positive for COVID-19 on Tuesday, the ministry said.
According to members of the government cabinet, Siza Vieira has "some symptoms" and will remain in isolation at home.
The minister has been in prophylactic isolation since Saturday, when he had contact with the finance minister, who was infected with the novel coronavirus.
Portuguese Minister of Labor and Social Security Ana Mendes Godinho also tested positive for COVID-19 on Monday.
Portugal registered Tuesday another 218 COVID-19 related deaths, setting a new daily record, with a total of 9,246 deaths in the country.
In addition, 10,455 new cases were registered, bringing the national tally to 566,958.
Portugal has entered a new two-week nationwide lockdown since Friday in a bid to fight the spread of the novel coronavirus.
As the world is struggling to contain the pandemic, vaccination is underway in some countries with the already-authorized coronavirus vaccines.
Meanwhile, 237 candidate vaccines are still being developed worldwide -- 64 of them in clinical trials -- in countries including Germany, China, Russia, Britain and the United States, according to information released by the World Health Organization on Jan. 15.