The fourth annual Santa Speedo Run featured almost 300 runners navigating a mile and a half course around West Peachtree and Peachtree streets.
Participants were asked to raise at least $250 to participate in the run. The event benefited CURE Childhood Cancer this year.
"Each year, the Atlanta Santa Speedo Run grows larger and more festive," event organizer Ted Tuerk said. "We all have a great time, but the best part is building a community and raising money for a worthwhile charity."
Wearing a Speedo or similar attire was required to participate. Other accessories included presents, Santa beards, elf ears, toy soldier hats, wreaths and stockings. One runner carried the characters from the "Rudolph the Red-Nose Reindeer" TV special.
Organizers believe the run raised almost $90,000 this year.
The Santa Speedo Run originated in Boston in 2000. It came to Atlanta in 2009.