The legislation, passed late on Tuesday, introduces the concept of “periodic meetings” for rallies organised repeatedly in the same place and on the same date, giving such gatherings priority over other meetings.
Under the new law, unrelated meetings must take place at least 100 metres away from any meeting designated “periodic”.
The ruling rightwing Law and Justice (PiS) party said the law would boost the security of participants at all gatherings by preventing clashes.
They claim the law will allow PiS to organise a monthly meeting, protected from counter-protests, to commemorate the 2010 Smolensk plane crash.
Ninety-six people died including president Lech Kaczyński, the twin brother of PiS head Jarosław Kaczyński.
Opposition politicians and rights activists claimed that the original proposals restricted fundamental rights and freedoms.
“Yesterday was a sad day for Poland because now there is a new law governing protests which limits the right of assembly,” Polish MEP Janusz Lewandowski said in Strasbourg. Lewandowski is a former Commissioner and member of Civic Platform, affiliated to the EPP group.
“Like all other EU citizens, Poles have the right to an independent judiciary… Polish women have freedom of choice, and Poles have the right to freedom of assembly, expression and thought,” Dutch ALDE MEP Sophia in’t Veld said.
PiS is affiliated with the ECR group, founded by Britain’s Tories.
Tens of thousands of Poles took to the streets across the country to protest the PiS government on Tuesday, the 35th anniversary of the martial law crackdown in Communist Poland.