Park officials said Marcin Bachleda-Blaszczak was reported missing on Aug. 24.
Bachleda-Blaszczak's vehicle was located in the Sugarlands Visitor Center parking lot.
Officials said his last known location was the Sugarlands Visitor Center parking lot on Aug. 22.
He is described to be 5 feet, 6 inches tall and approximately 170 pounds, with brown hair and blue eyes. He is from Illinois, it's not clear from what area.
Officials said a team of 57 park rangers and volunteers was actively searching areas in and around the park.
Anyone with information about Bachleda-Blaszczak's whereabouts, or who may have seen him in or around the park, is asked to contact GRSM_Dispatch@nps.gov.