She's now self-isolating in line with HSE guidelines.
Helen McEntee announced she's pregnant at the start of December - but the HSE's information to date shows pregnant women or their babies aren't at a higher risk if they get Covid-19.
The Justice Minister says she'll continue to carry out her duties by working from home - including attending cabinet.
She's also urged everyone to follow the public health advice and stay at home to protect the health system and the most vulnerable.
Helen McEntee is the second cabinet minister to be diagnosed with coronavirus - after Agriculture Minister Charlie McConalogue tested positive last month.