More than 25,000 people reportedly took to the streets of Dresden and other German cities on Monday for anti-Islamisation rallies.
The PEGIDA movement, or Patriotic Europeans Against the Islamisation of the West, organised the marches.
A week earlier, they had attracted some 18,000 followers to a similar demonstration in Dresden.
The group defied senior German politicians’ calls for people not to attend.
Chancellor Angela Merkel said the protest had been arranged by people with “hatred in their hearts.”
Meanwhile counter-rallies were held across Germany, including one in Dresden, which attracted 7,000 people, according to local police.
In Munich some 20,000 people turned out, while Leipzig city officials say 30,000 attended a march there.
Germany’s political leadership is keeping a close eye on the growth of anti-Islamisation groups.
On January 13 Angela Merkel is expected to attend a protest set up by Muslim organisations against the attacks in France.