Shafaq news/ Polish President Andrzej Duda was tested on Friday and found to be positive, Blazej Spychalski announced on Saturday.
He joins a handful of world leaders who have caught the virus, among them US President Donald Trump and UK PM Boris Johnson.
Poland faces a surge in the coronavirus pandemic, with a daily record of more than 13,600 new cases on Friday.
The country has now entered a nationwide "red zone" lockdown that includes the partial closure of primary schools and restaurants.
While it is unclear when Mr Duda contracted the virus, he had attended an event in Tallinn on Monday where he met Bulgarian President Rumen Radev who later went into quarantine.
"The president yesterday was tested for the presence of coronavirus," Mr Spychalski said on Twitter on Saturday.
"The result turned out to be positive. The president is fine. We are in constant contact with the relevant medical services."
Earlier this October, Poland's new education minister also tests positive.