National Route 31 is a national highway in South Korea connects Gijang, Busan to Singosan, Anbyeon.

Due to the separation of Korean peninsula, it de facto ends in Yanggu It established on 31 August 1971.

[1] Busan Ulsan North Gyeongsang Province Gangwon Province Kangwon North Hamgyeong IS: Intersection, IC: Interchange