Daniel Danc was last seen at around 5.15pm on Tuesday October 20 in the Mapplewell area of Barnsley.
He is believed to have been seen at Sheffield train station the next day, and family and friends are growing increasingly concerned for his welfare.
Daniel is Slovakian and is described as being around 5ft 10ins tall, of slim build, with brown eyes and black hair with a line shaved into it.
He was last seen wearing a blue Nike tracksuit with black Nike trainers. It is believed he also had a small bag with ‘D&G’ on it with him.
Daniel is known to frequent the Darnall area of Sheffield and has connections to the West Midlands area.
If you have seen Daniel, or know where he might be, please call South Yorkshire Police on 101 quoting incident number 1311 of 20 October 2015.