The actor announced the news on Instagram on Monday, which was also his 60th birthday.
His caption was written in Spanish and translated to English by CNN.
"Hello everyone, I want to make public that today, August 10, I am forced to celebrate my 60th birthday following quarantine, having tested positive with Covid-19 disease," Banderas wrote, alongside a photo of himself as a young child. "I would like to add that I feel relatively well, just a little more tired than usual and confident that I will recover as soon as possible following the medical indications that I hope will allow me to overcome the infectious process that I suffer and that is affecting so many people around the planet."