In over 4,800 cases, officers handed out fines. They also issued more than 1,100 reprimands to people not complying with rules that require Poles to cover their nose and mouth with a mask in public, state news agency PAP reported.
Deputy Interior Minister Maciej Wąsik told reporters on Monday that police carried out almost 30,000 checks over the weekend, including on public transport, at stores, restaurants, gyms and nightclubs.
Wąsik said police would be "intensifying their activities" in the days ahead in order to ensure "more compliance" with epidemic restrictions.
Poland went into a partial national lockdown for three weeks from Saturday amid a resurgence of COVID-19 cases.
Hotels, cinemas, theatres and sports facilities nationwide have been told to shut, while shopping malls are only allowed to sell essential items.
Poland on Monday reported 14,578 new coronavirus infections and 65 more deaths, bringing its total number of cases during the pandemic to 2,073,129 and fatalities to 49,365.