Kim enlisted in the army on 31 March 2015, the first five weeks spent for his mandatory basic training at the 1st Infantry Division (Republic of Korea) recruit training center in Gwangtan-myeon, Paju, Gyeonggi province. He later ended up as the top recruit among the 244 in his batch, earning the Excellence Award during the graduation ceremony. He was under the 55th Infantry Division in Cheoin-gu, Yongin to serve as an active-duty soldier for 21 months and was also a member of the military band. He was discharged on 30 December 2016.