완득이

Yoo Ah-in

Do Wan-deuk

Kim Yoon-seok

Lee Dong-joo

Park Soo-young

Wan-deuk's Father

Lee Jasmine

Wan-deuk's Mother

김영재

Nam Min-gu

Ahn Kil-kang

Coach

Park Hyo-joo

Lee Ho-jeong

강별

Jeong Yun-ha

Kim Dong-young

Hyeok-Ju

Jo Deok-jae

Director of Students

Sung Yoo-bin

Young Wan-deuk

Kim Sang-ho

Annoyed Neighbor