Porfirije has developed "very mild symptoms of the virus infection" and remains in home isolation, the statement said.
It added that Porfirije is carrying out administrative duties entirely without problems.
The 60-year-old patriarch became the head of the Serbian Orthodox Church after the previous patriarch, Irinej, died in November 2020 after contracting the coronavirus.
Porfirije on Sunday attended a mass ceremony in Republika Srpska, the Serb-run part of neighbouring Bosnia, where few people wore face masks.
Serbia reported nearly 9000 new infections on Monday in the country of seven million people.
The number of daily new cases has risen sharply after New Year's celebrations that included open-air concerts and relaxed anti-virus rules.
Experts say the current rise in cases is driven by the fast-spreading Omicron variant of the coronavirus and is likely to worsen further.Â
Epidemiologist Predrag Kon on Monday criticised the virus policies of authorities.
"Everything that was organised should not have happened," Kon said.
"Belgrade exploded after New Year's and now it's spreading to the rest of Serbia."
Serbia has recorded more than 1.3 million cases of infection since the start of the pandemic while nearly 13,000 people have died of COVID-19.
