Princess Madeleine is the youngest of King Carl XVI Gustaf and Queen Silvia's three children, The Local reported Monday.
She received bouquets from members of the public and listened to music from the army drum corps along with hundreds of people gathered in the palace's courtyard for her birthday gala Sunday.
One woman even risked getting a parking ticket by leaving her car right in front of the palace while she presented Madeleine with an orchid.
"I was lucky to have been able to get to the front despite all the people. I called her name and was able to hand over the flower," said Birgitta Bodin of Stockholm.
Princess Madeleine received the traditional Swedish four cheers before returning to the main palace with the rest of the royal family.
"The rest of the celebrations will be private," said palace spokeswoman Nina Eldh.