Officers detected breaches in several regions across the country including 25 people being found in a pub at 1.30am, and no masks being worn by staff.
Gardai carried out thousands of inspections over the weekend, and say they issued their first closure order after seeing breaches including not complying with serving a substantial meal.
The say the order followed repeated engagement by local Gardai.
In Dublin Gardai found up to 200 people in a pub with no food being served and no social distancing, while in another premises 25 people were found inside at 1.30am with fresh pints pulled.
In the southern region, 25 people were found in a pub after midnight, include the license holder sitting at a table with customers, while people at another table were huddled with their arms around each other.
20 people were found at a sports club in the east with no food, no chef present and the kitchen closed, while 30 people were found in a shebeen with no masks or social distancing.