President Aleksandar Vucic said the rally was the biggest the country had seen in decades. It follows months of protests against the ultranationalist-turned-liberal.
Tens of thousands of people gathered in Belgrade on Friday to show support for President Aleksandar Vucic, countering five months of weekly anti-government protests.
Critics accuse Vucic of being an autocrat who has overseen a gradual erosion of democratic rights in the small Balkan country.
But supporters from across Serbia and neighboring countries shouted slogans such as "support to Vucic" and "Aco (Aleksandar abbreviated) the Serb" as they marched through the capital.
Vucic said the rally was the biggest the country had seen in decades. State-run media outlets said there were more than 100,000 marchers. Independent outlets did not make any estimates.
The president, a former ultranationalist, has presented himself as a liberal and supports Serbia's accession to the European Union.
He has dismissed claims by the opposition, which has rallied against him every weekend since December, that he has tried to undermine democratic freedoms.
The European Commission criticized the Serbian government last year for its failure to adequately uphold press freedoms. It noted fears about threats and violence against journalists.
The opposition is expected to hold another round of protests on Saturday.
amp/kl (AFP, AP, Reuters)