For his mandatory military Service, Ryu was a member of the Seoul Metropolitan Police Agency from 2008 to 2010. After his discharge, Ryu returned to television in 2011 in the romantic comedy My Princess, and the popular family drama Ojakgyo Family. In 2013, he joined the reality/variety show Real Men, in which male celebrities visit army bases and experience daily life there. He also played a detective chasing a fugitive in Two Weeks (2013).