Austin Jones, from Bloomingdale in Illinois, is accused of instructing two female fans to send him sexually explicit videos of themselves.
The girls are said to be around 14 years old.
The singer appeared in Chicago federal court on Tuesday and could spend up to 30 years in jail if convicted.
Court documents state that Jones used Facebook to communicate with the fans.
The alternative pop vocalist is said to have a huge teen following with over half a million subscribers on his YouTube channel.
His hit covers – including songs by Justin Bieber, Twenty One Pilots and Fall Out Boy – have had millions of views online.
Hello from Poland ???????? pic.twitter.com/L2sKjSQbfm
— Austin Jones (@iAmAustinJones) June 8, 2017